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1=head1 NAME
2
3perlport - Writing portable Perl
4
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5=head1 DESCRIPTION
6
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7Perl runs on numerous operating systems. While most of them share
8much in common, they also have their own unique features.
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9
10This document is meant to help you to find out what constitutes portable
b7df3edc 11Perl code. That way once you make a decision to write portably,
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12you know where the lines are drawn, and you can stay within them.
13
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14There is a tradeoff between taking full advantage of one particular
15type of computer and taking advantage of a full range of them.
16Naturally, as you broaden your range and become more diverse, the
17common factors drop, and you are left with an increasingly smaller
18area of common ground in which you can operate to accomplish a
19particular task. Thus, when you begin attacking a problem, it is
20important to consider under which part of the tradeoff curve you
21want to operate. Specifically, you must decide whether it is
22important that the task that you are coding have the full generality
23of being portable, or whether to just get the job done right now.
24This is the hardest choice to be made. The rest is easy, because
25Perl provides many choices, whichever way you want to approach your
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26problem.
27
28Looking at it another way, writing portable code is usually about
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29willfully limiting your available choices. Naturally, it takes
30discipline and sacrifice to do that. The product of portability
31and convenience may be a constant. You have been warned.
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32
33Be aware of two important points:
34
35=over 4
36
37=item Not all Perl programs have to be portable
38
b7df3edc 39There is no reason you should not use Perl as a language to glue Unix
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40tools together, or to prototype a Macintosh application, or to manage the
41Windows registry. If it makes no sense to aim for portability for one
42reason or another in a given program, then don't bother.
43
b7df3edc 44=item Nearly all of Perl already I<is> portable
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45
46Don't be fooled into thinking that it is hard to create portable Perl
47code. It isn't. Perl tries its level-best to bridge the gaps between
48what's available on different platforms, and all the means available to
49use those features. Thus almost all Perl code runs on any machine
6ab3f9cb 50without modification. But there are some significant issues in
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51writing portable code, and this document is entirely about those issues.
52
53=back
54
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55Here's the general rule: When you approach a task commonly done
56using a whole range of platforms, think about writing portable
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57code. That way, you don't sacrifice much by way of the implementation
58choices you can avail yourself of, and at the same time you can give
59your users lots of platform choices. On the other hand, when you have to
60take advantage of some unique feature of a particular platform, as is
61often the case with systems programming (whether for Unix, Windows,
62S<Mac OS>, VMS, etc.), consider writing platform-specific code.
63
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64When the code will run on only two or three operating systems, you
65may need to consider only the differences of those particular systems.
66The important thing is to decide where the code will run and to be
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67deliberate in your decision.
68
69The material below is separated into three main sections: main issues of
70portability (L<"ISSUES">, platform-specific issues (L<"PLATFORMS">, and
b7df3edc 71built-in perl functions that behave differently on various ports
0a47030a 72(L<"FUNCTION IMPLEMENTATIONS">.
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73
74This information should not be considered complete; it includes possibly
b8099c3d 75transient information about idiosyncrasies of some of the ports, almost
b7df3edc 76all of which are in a state of constant evolution. Thus, this material
e41182b5 77should be considered a perpetual work in progress
cc07ed0b 78(C<< <IMG SRC="yellow_sign.gif" ALT="Under Construction"> >>).
e41182b5 79
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80=head1 ISSUES
81
82=head2 Newlines
83
638bc118 84In most operating systems, lines in files are terminated by newlines.
e41182b5 85Just what is used as a newline may vary from OS to OS. Unix
b7df3edc 86traditionally uses C<\012>, one type of DOSish I/O uses C<\015\012>,
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87and S<Mac OS> uses C<\015>.
88
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89Perl uses C<\n> to represent the "logical" newline, where what is
90logical may depend on the platform in use. In MacPerl, C<\n> always
91means C<\015>. In DOSish perls, C<\n> usually means C<\012>, but
92when accessing a file in "text" mode, STDIO translates it to (or
56d7751a 93from) C<\015\012>, depending on whether you're reading or writing.
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94Unix does the same thing on ttys in canonical mode. C<\015\012>
95is commonly referred to as CRLF.
96
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97A common cause of unportable programs is the misuse of chop() to trim
98newlines:
99
100 # XXX UNPORTABLE!
101 while(<FILE>) {
102 chop;
103 @array = split(/:/);
104 #...
105 }
106
107You can get away with this on Unix and MacOS (they have a single
108character end-of-line), but the same program will break under DOSish
109perls because you're only chop()ing half the end-of-line. Instead,
110chomp() should be used to trim newlines. The Dunce::Files module can
111help audit your code for misuses of chop().
112
113When dealing with binary files (or text files in binary mode) be sure
114to explicitly set $/ to the appropriate value for your file format
115before using chomp().
116
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117Because of the "text" mode translation, DOSish perls have limitations
118in using C<seek> and C<tell> on a file accessed in "text" mode.
119Stick to C<seek>-ing to locations you got from C<tell> (and no
120others), and you are usually free to use C<seek> and C<tell> even
121in "text" mode. Using C<seek> or C<tell> or other file operations
122may be non-portable. If you use C<binmode> on a file, however, you
123can usually C<seek> and C<tell> with arbitrary values in safety.
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124
125A common misconception in socket programming is that C<\n> eq C<\012>
0a47030a 126everywhere. When using protocols such as common Internet protocols,
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127C<\012> and C<\015> are called for specifically, and the values of
128the logical C<\n> and C<\r> (carriage return) are not reliable.
129
130 print SOCKET "Hi there, client!\r\n"; # WRONG
131 print SOCKET "Hi there, client!\015\012"; # RIGHT
132
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133However, using C<\015\012> (or C<\cM\cJ>, or C<\x0D\x0A>) can be tedious
134and unsightly, as well as confusing to those maintaining the code. As
6ab3f9cb 135such, the Socket module supplies the Right Thing for those who want it.
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136
137 use Socket qw(:DEFAULT :crlf);
138 print SOCKET "Hi there, client!$CRLF" # RIGHT
139
6ab3f9cb 140When reading from a socket, remember that the default input record
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141separator C<$/> is C<\n>, but robust socket code will recognize as
142either C<\012> or C<\015\012> as end of line:
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143
144 while (<SOCKET>) {
145 # ...
146 }
147
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148Because both CRLF and LF end in LF, the input record separator can
149be set to LF and any CR stripped later. Better to write:
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150
151 use Socket qw(:DEFAULT :crlf);
152 local($/) = LF; # not needed if $/ is already \012
153
154 while (<SOCKET>) {
155 s/$CR?$LF/\n/; # not sure if socket uses LF or CRLF, OK
156 # s/\015?\012/\n/; # same thing
157 }
158
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159This example is preferred over the previous one--even for Unix
160platforms--because now any C<\015>'s (C<\cM>'s) are stripped out
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161(and there was much rejoicing).
162
6ab3f9cb 163Similarly, functions that return text data--such as a function that
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164fetches a web page--should sometimes translate newlines before
165returning the data, if they've not yet been translated to the local
166newline representation. A single line of code will often suffice:
2ee0eb3c 167
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168 $data =~ s/\015?\012/\n/g;
169 return $data;
2ee0eb3c 170
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171Some of this may be confusing. Here's a handy reference to the ASCII CR
172and LF characters. You can print it out and stick it in your wallet.
173
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174 LF eq \012 eq \x0A eq \cJ eq chr(10) eq ASCII 10
175 CR eq \015 eq \x0D eq \cM eq chr(13) eq ASCII 13
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176
177 | Unix | DOS | Mac |
178 ---------------------------
179 \n | LF | LF | CR |
180 \r | CR | CR | LF |
181 \n * | LF | CRLF | CR |
182 \r * | CR | CR | LF |
183 ---------------------------
184 * text-mode STDIO
185
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186The Unix column assumes that you are not accessing a serial line
187(like a tty) in canonical mode. If you are, then CR on input becomes
188"\n", and "\n" on output becomes CRLF.
189
6ab3f9cb 190These are just the most common definitions of C<\n> and C<\r> in Perl.
aa7f90d3 191There may well be others. For example, on an EBCDIC implementation such
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192as z/OS or OS/400 the above material is similar to "Unix" but the code
193numbers change:
194
195 LF eq \025 eq \x15 eq chr(21) eq CP-1047 21
196 LF eq \045 eq \x25 eq \cU eq chr(37) eq CP-0037 37
197 CR eq \015 eq \x0D eq \cM eq chr(13) eq CP-1047 13
198 CR eq \015 eq \x0D eq \cM eq chr(13) eq CP-0037 13
199
200 | z/OS | OS/400 |
201 ----------------------
202 \n | LF | LF |
203 \r | CR | CR |
204 \n * | LF | LF |
205 \r * | CR | CR |
206 ----------------------
207 * text-mode STDIO
6ab3f9cb 208
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209=head2 Numbers endianness and Width
210
211Different CPUs store integers and floating point numbers in different
212orders (called I<endianness>) and widths (32-bit and 64-bit being the
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213most common today). This affects your programs when they attempt to transfer
214numbers in binary format from one CPU architecture to another,
215usually either "live" via network connection, or by storing the
216numbers to secondary storage such as a disk file or tape.
322422de 217
b7df3edc 218Conflicting storage orders make utter mess out of the numbers. If a
d1e3b762 219little-endian host (Intel, VAX) stores 0x12345678 (305419896 in
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220decimal), a big-endian host (Motorola, Sparc, PA) reads it as
2210x78563412 (2018915346 in decimal). Alpha and MIPS can be either:
222Digital/Compaq used/uses them in little-endian mode; SGI/Cray uses
223them in big-endian mode. To avoid this problem in network (socket)
224connections use the C<pack> and C<unpack> formats C<n> and C<N>, the
225"network" orders. These are guaranteed to be portable.
322422de 226
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227You can explore the endianness of your platform by unpacking a
228data structure packed in native format such as:
229
230 print unpack("h*", pack("s2", 1, 2)), "\n";
231 # '10002000' on e.g. Intel x86 or Alpha 21064 in little-endian mode
232 # '00100020' on e.g. Motorola 68040
233
234If you need to distinguish between endian architectures you could use
235either of the variables set like so:
236
237 $is_big_endian = unpack("h*", pack("s", 1)) =~ /01/;
4375e838 238 $is_little_endian = unpack("h*", pack("s", 1)) =~ /^1/;
d1e3b762 239
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240Differing widths can cause truncation even between platforms of equal
241endianness. The platform of shorter width loses the upper parts of the
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242number. There is no good solution for this problem except to avoid
243transferring or storing raw binary numbers.
244
b7df3edc 245One can circumnavigate both these problems in two ways. Either
322422de 246transfer and store numbers always in text format, instead of raw
b7df3edc 247binary, or else consider using modules like Data::Dumper (included in
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248the standard distribution as of Perl 5.005) and Storable (included as
249of perl 5.8). Keeping all data as text significantly simplifies matters.
322422de 250
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251The v-strings are portable only up to v2147483647 (0x7FFFFFFF), that's
252how far EBCDIC, or more precisely UTF-EBCDIC will go.
253
433acd8a 254=head2 Files and Filesystems
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255
256Most platforms these days structure files in a hierarchical fashion.
b7df3edc 257So, it is reasonably safe to assume that all platforms support the
6ab3f9cb 258notion of a "path" to uniquely identify a file on the system. How
b7df3edc 259that path is really written, though, differs considerably.
e41182b5 260
4375e838 261Although similar, file path specifications differ between Unix,
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262Windows, S<Mac OS>, OS/2, VMS, VOS, S<RISC OS>, and probably others.
263Unix, for example, is one of the few OSes that has the elegant idea
264of a single root directory.
322422de 265
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266DOS, OS/2, VMS, VOS, and Windows can work similarly to Unix with C</>
267as path separator, or in their own idiosyncratic ways (such as having
268several root directories and various "unrooted" device files such NIL:
269and LPT:).
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270
271S<Mac OS> uses C<:> as a path separator instead of C</>.
272
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273The filesystem may support neither hard links (C<link>) nor
274symbolic links (C<symlink>, C<readlink>, C<lstat>).
433acd8a 275
6ab3f9cb 276The filesystem may support neither access timestamp nor change
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277timestamp (meaning that about the only portable timestamp is the
278modification timestamp), or one second granularity of any timestamps
279(e.g. the FAT filesystem limits the time granularity to two seconds).
280
74555b7a 281The "inode change timestamp" (the C<-C> filetest) may really be the
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282"creation timestamp" (which it is not in UNIX).
283
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284VOS perl can emulate Unix filenames with C</> as path separator. The
285native pathname characters greater-than, less-than, number-sign, and
286percent-sign are always accepted.
287
6ab3f9cb 288S<RISC OS> perl can emulate Unix filenames with C</> as path
322422de 289separator, or go native and use C<.> for path separator and C<:> to
6ab3f9cb 290signal filesystems and disk names.
e41182b5 291
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292Don't assume UNIX filesystem access semantics: that read, write,
293and execute are all the permissions there are, and even if they exist,
294that their semantics (for example what do r, w, and x mean on
295a directory) are the UNIX ones. The various UNIX/POSIX compatibility
296layers usually try to make interfaces like chmod() work, but sometimes
297there simply is no good mapping.
298
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299If all this is intimidating, have no (well, maybe only a little)
300fear. There are modules that can help. The File::Spec modules
301provide methods to do the Right Thing on whatever platform happens
302to be running the program.
e41182b5 303
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304 use File::Spec::Functions;
305 chdir(updir()); # go up one directory
306 $file = catfile(curdir(), 'temp', 'file.txt');
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307 # on Unix and Win32, './temp/file.txt'
308 # on Mac OS, ':temp:file.txt'
d1e3b762 309 # on VMS, '[.temp]file.txt'
e41182b5 310
b7df3edc 311File::Spec is available in the standard distribution as of version
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3125.004_05. File::Spec::Functions is only in File::Spec 0.7 and later,
313and some versions of perl come with version 0.6. If File::Spec
314is not updated to 0.7 or later, you must use the object-oriented
315interface from File::Spec (or upgrade File::Spec).
e41182b5 316
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317In general, production code should not have file paths hardcoded.
318Making them user-supplied or read from a configuration file is
319better, keeping in mind that file path syntax varies on different
320machines.
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321
322This is especially noticeable in scripts like Makefiles and test suites,
323which often assume C</> as a path separator for subdirectories.
324
b7df3edc 325Also of use is File::Basename from the standard distribution, which
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326splits a pathname into pieces (base filename, full path to directory,
327and file suffix).
328
19799a22 329Even when on a single platform (if you can call Unix a single platform),
b7df3edc 330remember not to count on the existence or the contents of particular
3c075c7d 331system-specific files or directories, like F</etc/passwd>,
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332F</etc/sendmail.conf>, F</etc/resolv.conf>, or even F</tmp/>. For
333example, F</etc/passwd> may exist but not contain the encrypted
334passwords, because the system is using some form of enhanced security.
335Or it may not contain all the accounts, because the system is using NIS.
3c075c7d 336If code does need to rely on such a file, include a description of the
b7df3edc 337file and its format in the code's documentation, then make it easy for
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338the user to override the default location of the file.
339
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340Don't assume a text file will end with a newline. They should,
341but people forget.
e41182b5 342
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343Do not have two files or directories of the same name with different
344case, like F<test.pl> and F<Test.pl>, as many platforms have
345case-insensitive (or at least case-forgiving) filenames. Also, try
346not to have non-word characters (except for C<.>) in the names, and
347keep them to the 8.3 convention, for maximum portability, onerous a
348burden though this may appear.
dd9f0070 349
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350Likewise, when using the AutoSplit module, try to keep your functions to
3518.3 naming and case-insensitive conventions; or, at the least,
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352make it so the resulting files have a unique (case-insensitively)
353first 8 characters.
354
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355Whitespace in filenames is tolerated on most systems, but not all,
356and even on systems where it might be tolerated, some utilities
fe829689 357might become confused by such whitespace.
ec481373 358
b7df3edc 359Many systems (DOS, VMS) cannot have more than one C<.> in their filenames.
433acd8a 360
c47ff5f1 361Don't assume C<< > >> won't be the first character of a filename.
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362Always use C<< < >> explicitly to open a file for reading, or even
363better, use the three-arg version of open, unless you want the user to
364be able to specify a pipe open.
0a47030a 365
fe829689 366 open(FILE, '<', $existing_file) or die $!;
0a47030a 367
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368If filenames might use strange characters, it is safest to open it
369with C<sysopen> instead of C<open>. C<open> is magic and can
c47ff5f1 370translate characters like C<< > >>, C<< < >>, and C<|>, which may
b7df3edc 371be the wrong thing to do. (Sometimes, though, it's the right thing.)
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372Three-arg open can also help protect against this translation in cases
373where it is undesirable.
e41182b5 374
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375Don't use C<:> as a part of a filename since many systems use that for
376their own semantics (MacOS Classic for separating pathname components,
377many networking schemes and utilities for separating the nodename and
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378the pathname, and so on). For the same reasons, avoid C<@>, C<;> and
379C<|>.
ec481373 380
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381Don't assume that in pathnames you can collapse two leading slashes
382C<//> into one: some networking and clustering filesystems have special
383semantics for that. Let the operating system to sort it out.
384
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385The I<portable filename characters> as defined by ANSI C are
386
387 a b c d e f g h i j k l m n o p q r t u v w x y z
388 A B C D E F G H I J K L M N O P Q R T U V W X Y Z
389 0 1 2 3 4 5 6 7 8 9
390 . _ -
391
08fef530 392and the "-" shouldn't be the first character. If you want to be
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393hypercorrect, stay case-insensitive and within the 8.3 naming
394convention (all the files and directories have to be unique within one
395directory if their names are lowercased and truncated to eight
396characters before the C<.>, if any, and to three characters after the
397C<.>, if any). (And do not use C<.>s in directory names.)
ec481373 398
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399=head2 System Interaction
400
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401Not all platforms provide a command line. These are usually platforms
402that rely primarily on a Graphical User Interface (GUI) for user
403interaction. A program requiring a command line interface might
404not work everywhere. This is probably for the user of the program
405to deal with, so don't stay up late worrying about it.
e41182b5 406
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407Some platforms can't delete or rename files held open by the system.
408Remember to C<close> files when you are done with them. Don't
409C<unlink> or C<rename> an open file. Don't C<tie> or C<open> a
410file already tied or opened; C<untie> or C<close> it first.
e41182b5 411
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412Don't open the same file more than once at a time for writing, as some
413operating systems put mandatory locks on such files.
414
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415Don't assume that write/modify permission on a directory gives the
416right to add or delete files/directories in that directory. That is
417filesystem specific: in some filesystems you need write/modify
418permission also (or even just) in the file/directory itself. In some
419filesystems (AFS, DFS) the permission to add/delete directory entries
420is a completely separate permission.
421
422Don't assume that a single C<unlink> completely gets rid of the file:
423some filesystems (most notably the ones in VMS) have versioned
424filesystems, and unlink() removes only the most recent one (it doesn't
425remove all the versions because by default the native tools on those
426platforms remove just the most recent version, too). The portable
427idiom to remove all the versions of a file is
428
94bb614c 429 1 while unlink "file";
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430
431This will terminate if the file is undeleteable for some reason
432(protected, not there, and so on).
433
e41182b5 434Don't count on a specific environment variable existing in C<%ENV>.
0a47030a 435Don't count on C<%ENV> entries being case-sensitive, or even
4a0d0822 436case-preserving. Don't try to clear %ENV by saying C<%ENV = ();>, or,
6be8f7a6 437if you really have to, make it conditional on C<$^O ne 'VMS'> since in
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438VMS the C<%ENV> table is much more than a per-process key-value string
439table.
e41182b5 440
d1e3b762 441Don't count on signals or C<%SIG> for anything.
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442
443Don't count on filename globbing. Use C<opendir>, C<readdir>, and
444C<closedir> instead.
445
b8099c3d 446Don't count on per-program environment variables, or per-program current
dd9f0070 447directories.
b8099c3d 448
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449Don't count on specific values of C<$!>.
450
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451=head2 Command names versus file pathnames
452
453Don't assume that the name used to invoke a command or program with
454C<system> or C<exec> can also be used to test for the existence of the
455file that holds the executable code for that command or program.
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456First, many systems have "internal" commands that are built-in to the
457shell or OS and while these commands can be invoked, there is no
458corresponding file. Second, some operating systems (e.g., Cygwin,
459DJGPP, OS/2, and VOS) have required suffixes for executable files;
460these suffixes are generally permitted on the command name but are not
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461required. Thus, a command like "perl" might exist in a file named
462"perl", "perl.exe", or "perl.pm", depending on the operating system.
463The variable "_exe" in the Config module holds the executable suffix,
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464if any. Third, the VMS port carefully sets up $^X and
465$Config{perlpath} so that no further processing is required. This is
466just as well, because the matching regular expression used below would
467then have to deal with a possible trailing version number in the VMS
468file name.
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469
470To convert $^X to a file pathname, taking account of the requirements
471of the various operating system possibilities, say:
472 use Config;
a10d74f3 473 $thisperl = $^X;
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474 if ($^O ne 'VMS')
475 {$thisperl .= $Config{_exe} unless $thisperl =~ m/$Config{_exe}$/i;}
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476
477To convert $Config{perlpath} to a file pathname, say:
a10d74f3 478 use Config;
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479 $thisperl = $Config{perlpath};
480 if ($^O ne 'VMS')
481 {$thisperl .= $Config{_exe} unless $thisperl =~ m/$Config{_exe}$/i;}
a10d74f3 482
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483=head2 Interprocess Communication (IPC)
484
b7df3edc
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485In general, don't directly access the system in code meant to be
486portable. That means, no C<system>, C<exec>, C<fork>, C<pipe>,
487C<``>, C<qx//>, C<open> with a C<|>, nor any of the other things
488that makes being a perl hacker worth being.
e41182b5
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489
490Commands that launch external processes are generally supported on
b7df3edc
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491most platforms (though many of them do not support any type of
492forking). The problem with using them arises from what you invoke
493them on. External tools are often named differently on different
4375e838 494platforms, may not be available in the same location, might accept
b7df3edc
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495different arguments, can behave differently, and often present their
496results in a platform-dependent way. Thus, you should seldom depend
497on them to produce consistent results. (Then again, if you're calling
498I<netstat -a>, you probably don't expect it to run on both Unix and CP/M.)
e41182b5 499
b7df3edc 500One especially common bit of Perl code is opening a pipe to B<sendmail>:
e41182b5 501
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502 open(MAIL, '|/usr/lib/sendmail -t')
503 or die "cannot fork sendmail: $!";
e41182b5
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504
505This is fine for systems programming when sendmail is known to be
506available. But it is not fine for many non-Unix systems, and even
507some Unix systems that may not have sendmail installed. If a portable
b7df3edc
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508solution is needed, see the various distributions on CPAN that deal
509with it. Mail::Mailer and Mail::Send in the MailTools distribution are
510commonly used, and provide several mailing methods, including mail,
511sendmail, and direct SMTP (via Net::SMTP) if a mail transfer agent is
512not available. Mail::Sendmail is a standalone module that provides
513simple, platform-independent mailing.
514
515The Unix System V IPC (C<msg*(), sem*(), shm*()>) is not available
516even on all Unix platforms.
e41182b5 517
a81e5e2e
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518Do not use either the bare result of C<pack("N", 10, 20, 30, 40)> or
519bare v-strings (such as C<v10.20.30.40>) to represent IPv4 addresses:
520both forms just pack the four bytes into network order. That this
521would be equal to the C language C<in_addr> struct (which is what the
522socket code internally uses) is not guaranteed. To be portable use
523the routines of the Socket extension, such as C<inet_aton()>,
524C<inet_ntoa()>, and C<sockaddr_in()>.
6b2463a0 525
e41182b5 526The rule of thumb for portable code is: Do it all in portable Perl, or
0a47030a
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527use a module (that may internally implement it with platform-specific
528code, but expose a common interface).
e41182b5 529
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530=head2 External Subroutines (XS)
531
b7df3edc 532XS code can usually be made to work with any platform, but dependent
e41182b5
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533libraries, header files, etc., might not be readily available or
534portable, or the XS code itself might be platform-specific, just as Perl
535code might be. If the libraries and headers are portable, then it is
536normally reasonable to make sure the XS code is portable, too.
537
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538A different type of portability issue arises when writing XS code:
539availability of a C compiler on the end-user's system. C brings
540with it its own portability issues, and writing XS code will expose
541you to some of those. Writing purely in Perl is an easier way to
e41182b5
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542achieve portability.
543
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544=head2 Standard Modules
545
546In general, the standard modules work across platforms. Notable
6ab3f9cb 547exceptions are the CPAN module (which currently makes connections to external
e41182b5 548programs that may not be available), platform-specific modules (like
6ab3f9cb 549ExtUtils::MM_VMS), and DBM modules.
e41182b5 550
b7df3edc 551There is no one DBM module available on all platforms.
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552SDBM_File and the others are generally available on all Unix and DOSish
553ports, but not in MacPerl, where only NBDM_File and DB_File are
0a47030a 554available.
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555
556The good news is that at least some DBM module should be available, and
6ab3f9cb 557AnyDBM_File will use whichever module it can find. Of course, then
b7df3edc
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558the code needs to be fairly strict, dropping to the greatest common
559factor (e.g., not exceeding 1K for each record), so that it will
6ab3f9cb 560work with any DBM module. See L<AnyDBM_File> for more details.
e41182b5 561
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562=head2 Time and Date
563
0a47030a 564The system's notion of time of day and calendar date is controlled in
b7df3edc 565widely different ways. Don't assume the timezone is stored in C<$ENV{TZ}>,
0a47030a
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566and even if it is, don't assume that you can control the timezone through
567that variable.
e41182b5 568
322422de 569Don't assume that the epoch starts at 00:00:00, January 1, 1970,
6ab3f9cb
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570because that is OS- and implementation-specific. It is better to store a date
571in an unambiguous representation. The ISO-8601 standard defines
572"YYYY-MM-DD" as the date format. A text representation (like "1987-12-18")
573can be easily converted into an OS-specific value using a module like
574Date::Parse. An array of values, such as those returned by
322422de 575C<localtime>, can be converted to an OS-specific representation using
6ab3f9cb 576Time::Local.
322422de 577
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578When calculating specific times, such as for tests in time or date modules,
579it may be appropriate to calculate an offset for the epoch.
b7df3edc 580
19799a22
GS
581 require Time::Local;
582 $offset = Time::Local::timegm(0, 0, 0, 1, 0, 70);
b7df3edc 583
19799a22
GS
584The value for C<$offset> in Unix will be C<0>, but in Mac OS will be
585some large number. C<$offset> can then be added to a Unix time value
586to get what should be the proper value on any system.
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587
588=head2 Character sets and character encoding
589
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590Assume very little about character sets.
591
592Assume nothing about numerical values (C<ord>, C<chr>) of characters.
593Do not use explicit code point ranges (like \xHH-\xHH); use for
594example symbolic character classes like C<[:print:]>.
595
596Do not assume that the alphabetic characters are encoded contiguously
597(in the numeric sense). There may be gaps.
598
599Do not assume anything about the ordering of the characters.
600The lowercase letters may come before or after the uppercase letters;
601the lowercase and uppercase may be interlaced so that both `a' and `A'
602come before `b'; the accented and other international characters may
603be interlaced so that E<auml> comes before `b'.
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604
605=head2 Internationalisation
606
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607If you may assume POSIX (a rather large assumption), you may read
608more about the POSIX locale system from L<perllocale>. The locale
609system at least attempts to make things a little bit more portable,
610or at least more convenient and native-friendly for non-English
611users. The system affects character sets and encoding, and date
612and time formatting--amongst other things.
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613
614=head2 System Resources
615
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616If your code is destined for systems with severely constrained (or
617missing!) virtual memory systems then you want to be I<especially> mindful
618of avoiding wasteful constructs such as:
e41182b5
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619
620 # NOTE: this is no longer "bad" in perl5.005
621 for (0..10000000) {} # bad
622 for (my $x = 0; $x <= 10000000; ++$x) {} # good
623
624 @lines = <VERY_LARGE_FILE>; # bad
625
626 while (<FILE>) {$file .= $_} # sometimes bad
0a47030a 627 $file = join('', <FILE>); # better
e41182b5 628
b7df3edc
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629The last two constructs may appear unintuitive to most people. The
630first repeatedly grows a string, whereas the second allocates a
631large chunk of memory in one go. On some systems, the second is
632more efficient that the first.
0a47030a 633
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634=head2 Security
635
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636Most multi-user platforms provide basic levels of security, usually
637implemented at the filesystem level. Some, however, do
a1667ba3 638not-- unfortunately. Thus the notion of user id, or "home" directory,
b7df3edc
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639or even the state of being logged-in, may be unrecognizable on many
640platforms. If you write programs that are security-conscious, it
641is usually best to know what type of system you will be running
642under so that you can write code explicitly for that platform (or
643class of platforms).
0a47030a 644
a1667ba3
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645Don't assume the UNIX filesystem access semantics: the operating
646system or the filesystem may be using some ACL systems, which are
647richer languages than the usual rwx. Even if the rwx exist,
648their semantics might be different.
649
650(From security viewpoint testing for permissions before attempting to
651do something is silly anyway: if one tries this, there is potential
652for race conditions-- someone or something might change the
653permissions between the permissions check and the actual operation.
654Just try the operation.)
655
656Don't assume the UNIX user and group semantics: especially, don't
2edcc0d9 657expect the C<< $< >> and C<< $> >> (or the C<$(> and C<$)>) to work
a1667ba3
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658for switching identities (or memberships).
659
660Don't assume set-uid and set-gid semantics. (And even if you do,
661think twice: set-uid and set-gid are a known can of security worms.)
662
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663=head2 Style
664
665For those times when it is necessary to have platform-specific code,
666consider keeping the platform-specific code in one place, making porting
6ab3f9cb 667to other platforms easier. Use the Config module and the special
0a47030a
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668variable C<$^O> to differentiate platforms, as described in
669L<"PLATFORMS">.
e41182b5 670
b7df3edc
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671Be careful in the tests you supply with your module or programs.
672Module code may be fully portable, but its tests might not be. This
673often happens when tests spawn off other processes or call external
674programs to aid in the testing, or when (as noted above) the tests
675assume certain things about the filesystem and paths. Be careful
676not to depend on a specific output style for errors, such as when
d1be9408 677checking C<$!> after a system call. Some platforms expect a certain
b7df3edc
GS
678output format, and perl on those platforms may have been adjusted
679accordingly. Most specifically, don't anchor a regex when testing
680an error value.
e41182b5 681
0a47030a 682=head1 CPAN Testers
e41182b5 683
0a47030a
GS
684Modules uploaded to CPAN are tested by a variety of volunteers on
685different platforms. These CPAN testers are notified by mail of each
e41182b5 686new upload, and reply to the list with PASS, FAIL, NA (not applicable to
0a47030a 687this platform), or UNKNOWN (unknown), along with any relevant notations.
e41182b5
GS
688
689The purpose of the testing is twofold: one, to help developers fix any
0a47030a 690problems in their code that crop up because of lack of testing on other
b7df3edc 691platforms; two, to provide users with information about whether
0a47030a 692a given module works on a given platform.
e41182b5
GS
693
694=over 4
695
696=item Mailing list: cpan-testers@perl.org
697
c997b287 698=item Testing results: http://testers.cpan.org/
e41182b5
GS
699
700=back
701
e41182b5
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702=head1 PLATFORMS
703
704As of version 5.002, Perl is built with a C<$^O> variable that
705indicates the operating system it was built on. This was implemented
b7df3edc
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706to help speed up code that would otherwise have to C<use Config>
707and use the value of C<$Config{osname}>. Of course, to get more
e41182b5
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708detailed information about the system, looking into C<%Config> is
709certainly recommended.
710
b7df3edc
GS
711C<%Config> cannot always be trusted, however, because it was built
712at compile time. If perl was built in one place, then transferred
713elsewhere, some values may be wrong. The values may even have been
714edited after the fact.
6ab3f9cb 715
e41182b5
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716=head2 Unix
717
718Perl works on a bewildering variety of Unix and Unix-like platforms (see
719e.g. most of the files in the F<hints/> directory in the source code kit).
720On most of these systems, the value of C<$^O> (hence C<$Config{'osname'}>,
d1e3b762
GS
721too) is determined either by lowercasing and stripping punctuation from the
722first field of the string returned by typing C<uname -a> (or a similar command)
723at the shell prompt or by testing the file system for the presence of
724uniquely named files such as a kernel or header file. Here, for example,
725are a few of the more popular Unix flavors:
e41182b5 726
b7df3edc 727 uname $^O $Config{'archname'}
6ab3f9cb 728 --------------------------------------------
b7df3edc 729 AIX aix aix
6ab3f9cb 730 BSD/OS bsdos i386-bsdos
e1516da7 731 Darwin darwin darwin
6ab3f9cb
GS
732 dgux dgux AViiON-dgux
733 DYNIX/ptx dynixptx i386-dynixptx
b7df3edc 734 FreeBSD freebsd freebsd-i386
d1e3b762 735 Linux linux arm-linux
b7df3edc 736 Linux linux i386-linux
6ab3f9cb
GS
737 Linux linux i586-linux
738 Linux linux ppc-linux
b7df3edc
GS
739 HP-UX hpux PA-RISC1.1
740 IRIX irix irix
b787fad4 741 Mac OS X darwin darwin
d1e3b762
GS
742 MachTen PPC machten powerpc-machten
743 NeXT 3 next next-fat
744 NeXT 4 next OPENSTEP-Mach
6ab3f9cb 745 openbsd openbsd i386-openbsd
b7df3edc 746 OSF1 dec_osf alpha-dec_osf
6ab3f9cb
GS
747 reliantunix-n svr4 RM400-svr4
748 SCO_SV sco_sv i386-sco_sv
749 SINIX-N svr4 RM400-svr4
750 sn4609 unicos CRAY_C90-unicos
751 sn6521 unicosmk t3e-unicosmk
752 sn9617 unicos CRAY_J90-unicos
b7df3edc
GS
753 SunOS solaris sun4-solaris
754 SunOS solaris i86pc-solaris
755 SunOS4 sunos sun4-sunos
e41182b5 756
b7df3edc
GS
757Because the value of C<$Config{archname}> may depend on the
758hardware architecture, it can vary more than the value of C<$^O>.
6ab3f9cb 759
e41182b5
GS
760=head2 DOS and Derivatives
761
b7df3edc 762Perl has long been ported to Intel-style microcomputers running under
e41182b5
GS
763systems like PC-DOS, MS-DOS, OS/2, and most Windows platforms you can
764bring yourself to mention (except for Windows CE, if you count that).
b7df3edc 765Users familiar with I<COMMAND.COM> or I<CMD.EXE> style shells should
e41182b5
GS
766be aware that each of these file specifications may have subtle
767differences:
768
769 $filespec0 = "c:/foo/bar/file.txt";
770 $filespec1 = "c:\\foo\\bar\\file.txt";
771 $filespec2 = 'c:\foo\bar\file.txt';
772 $filespec3 = 'c:\\foo\\bar\\file.txt';
773
b7df3edc
GS
774System calls accept either C</> or C<\> as the path separator.
775However, many command-line utilities of DOS vintage treat C</> as
776the option prefix, so may get confused by filenames containing C</>.
777Aside from calling any external programs, C</> will work just fine,
778and probably better, as it is more consistent with popular usage,
779and avoids the problem of remembering what to backwhack and what
780not to.
e41182b5 781
b7df3edc
GS
782The DOS FAT filesystem can accommodate only "8.3" style filenames. Under
783the "case-insensitive, but case-preserving" HPFS (OS/2) and NTFS (NT)
0a47030a 784filesystems you may have to be careful about case returned with functions
e41182b5
GS
785like C<readdir> or used with functions like C<open> or C<opendir>.
786
b7df3edc
GS
787DOS also treats several filenames as special, such as AUX, PRN,
788NUL, CON, COM1, LPT1, LPT2, etc. Unfortunately, sometimes these
789filenames won't even work if you include an explicit directory
790prefix. It is best to avoid such filenames, if you want your code
791to be portable to DOS and its derivatives. It's hard to know what
792these all are, unfortunately.
e41182b5
GS
793
794Users of these operating systems may also wish to make use of
b7df3edc 795scripts such as I<pl2bat.bat> or I<pl2cmd> to
e41182b5
GS
796put wrappers around your scripts.
797
798Newline (C<\n>) is translated as C<\015\012> by STDIO when reading from
6ab3f9cb
GS
799and writing to files (see L<"Newlines">). C<binmode(FILEHANDLE)>
800will keep C<\n> translated as C<\012> for that filehandle. Since it is a
801no-op on other systems, C<binmode> should be used for cross-platform code
b7df3edc
GS
802that deals with binary data. That's assuming you realize in advance
803that your data is in binary. General-purpose programs should
804often assume nothing about their data.
e41182b5 805
b7df3edc 806The C<$^O> variable and the C<$Config{archname}> values for various
e41182b5
GS
807DOSish perls are as follows:
808
67ac489e
MS
809 OS $^O $Config{archname} ID Version
810 --------------------------------------------------------
811 MS-DOS dos ?
812 PC-DOS dos ?
813 OS/2 os2 ?
814 Windows 3.1 ? ? 0 3 01
815 Windows 95 MSWin32 MSWin32-x86 1 4 00
816 Windows 98 MSWin32 MSWin32-x86 1 4 10
817 Windows ME MSWin32 MSWin32-x86 1 ?
818 Windows NT MSWin32 MSWin32-x86 2 4 xx
819 Windows NT MSWin32 MSWin32-ALPHA 2 4 xx
820 Windows NT MSWin32 MSWin32-ppc 2 4 xx
821 Windows 2000 MSWin32 MSWin32-x86 2 5 xx
822 Windows XP MSWin32 MSWin32-x86 2 ?
823 Windows CE MSWin32 ? 3
824 Cygwin cygwin ?
e41182b5 825
34aaaa84
PP
826The various MSWin32 Perl's can distinguish the OS they are running on
827via the value of the fifth element of the list returned from
828Win32::GetOSVersion(). For example:
829
830 if ($^O eq 'MSWin32') {
831 my @os_version_info = Win32::GetOSVersion();
832 print +('3.1','95','NT')[$os_version_info[4]],"\n";
833 }
834
e41182b5
GS
835Also see:
836
837=over 4
838
c997b287 839=item *
e41182b5 840
c997b287
GS
841The djgpp environment for DOS, http://www.delorie.com/djgpp/
842and L<perldos>.
e41182b5 843
c997b287 844=item *
e41182b5 845
c997b287
GS
846The EMX environment for DOS, OS/2, etc. emx@iaehv.nl,
847http://www.leo.org/pub/comp/os/os2/leo/gnu/emx+gcc/index.html or
f224927c 848ftp://hobbes.nmsu.edu/pub/os2/dev/emx/ Also L<perlos2>.
e41182b5 849
c997b287 850=item *
d1e3b762 851
c997b287
GS
852Build instructions for Win32 in L<perlwin32>, or under the Cygnus environment
853in L<perlcygwin>.
854
855=item *
856
857The C<Win32::*> modules in L<Win32>.
858
859=item *
860
861The ActiveState Pages, http://www.activestate.com/
862
863=item *
864
865The Cygwin environment for Win32; F<README.cygwin> (installed
47dafe4d 866as L<perlcygwin>), http://www.cygwin.com/
c997b287
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867
868=item *
869
870The U/WIN environment for Win32,
cea6626f 871http://www.research.att.com/sw/tools/uwin/
c997b287 872
cea6626f 873=item *
d1e3b762 874
cea6626f 875Build instructions for OS/2, L<perlos2>
d1e3b762 876
e41182b5
GS
877=back
878
dd9f0070 879=head2 S<Mac OS>
e41182b5
GS
880
881Any module requiring XS compilation is right out for most people, because
882MacPerl is built using non-free (and non-cheap!) compilers. Some XS
883modules that can work with MacPerl are built and distributed in binary
6ab3f9cb 884form on CPAN.
e41182b5
GS
885
886Directories are specified as:
887
888 volume:folder:file for absolute pathnames
889 volume:folder: for absolute pathnames
890 :folder:file for relative pathnames
891 :folder: for relative pathnames
892 :file for relative pathnames
893 file for relative pathnames
894
b7df3edc 895Files are stored in the directory in alphabetical order. Filenames are
6ab3f9cb 896limited to 31 characters, and may include any character except for
b7df3edc 897null and C<:>, which is reserved as the path separator.
e41182b5 898
0a47030a 899Instead of C<flock>, see C<FSpSetFLock> and C<FSpRstFLock> in the
6ab3f9cb 900Mac::Files module, or C<chmod(0444, ...)> and C<chmod(0666, ...)>.
e41182b5
GS
901
902In the MacPerl application, you can't run a program from the command line;
903programs that expect C<@ARGV> to be populated can be edited with something
904like the following, which brings up a dialog box asking for the command
905line arguments.
906
907 if (!@ARGV) {
908 @ARGV = split /\s+/, MacPerl::Ask('Arguments?');
909 }
910
b7df3edc 911A MacPerl script saved as a "droplet" will populate C<@ARGV> with the full
e41182b5
GS
912pathnames of the files dropped onto the script.
913
b7df3edc
GS
914Mac users can run programs under a type of command line interface
915under MPW (Macintosh Programmer's Workshop, a free development
916environment from Apple). MacPerl was first introduced as an MPW
917tool, and MPW can be used like a shell:
e41182b5
GS
918
919 perl myscript.plx some arguments
920
921ToolServer is another app from Apple that provides access to MPW tools
0a47030a 922from MPW and the MacPerl app, which allows MacPerl programs to use
e41182b5
GS
923C<system>, backticks, and piped C<open>.
924
925"S<Mac OS>" is the proper name for the operating system, but the value
926in C<$^O> is "MacOS". To determine architecture, version, or whether
927the application or MPW tool version is running, check:
928
929 $is_app = $MacPerl::Version =~ /App/;
930 $is_tool = $MacPerl::Version =~ /MPW/;
931 ($version) = $MacPerl::Version =~ /^(\S+)/;
932 $is_ppc = $MacPerl::Architecture eq 'MacPPC';
933 $is_68k = $MacPerl::Architecture eq 'Mac68K';
934
b787fad4
JH
935S<Mac OS X>, based on NeXT's OpenStep OS, runs MacPerl natively, under the
936"Classic" environment. There is no "Carbon" version of MacPerl to run
937under the primary Mac OS X environment. S<Mac OS X> and its Open Source
938version, Darwin, both run Unix perl natively.
6ab3f9cb 939
e41182b5
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940Also see:
941
942=over 4
943
c997b287
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944=item *
945
862b5365 946MacPerl Development, http://dev.macperl.org/ .
c997b287
GS
947
948=item *
949
862b5365 950The MacPerl Pages, http://www.macperl.com/ .
e41182b5 951
c997b287 952=item *
6ab3f9cb 953
862b5365 954The MacPerl mailing lists, http://lists.perl.org/ .
e41182b5
GS
955
956=back
957
e41182b5
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958=head2 VMS
959
c997b287 960Perl on VMS is discussed in L<perlvms> in the perl distribution.
b7df3edc 961Perl on VMS can accept either VMS- or Unix-style file
e41182b5
GS
962specifications as in either of the following:
963
964 $ perl -ne "print if /perl_setup/i" SYS$LOGIN:LOGIN.COM
965 $ perl -ne "print if /perl_setup/i" /sys$login/login.com
966
967but not a mixture of both as in:
968
969 $ perl -ne "print if /perl_setup/i" sys$login:/login.com
970 Can't open sys$login:/login.com: file specification syntax error
971
972Interacting with Perl from the Digital Command Language (DCL) shell
973often requires a different set of quotation marks than Unix shells do.
974For example:
975
976 $ perl -e "print ""Hello, world.\n"""
977 Hello, world.
978
b7df3edc 979There are several ways to wrap your perl scripts in DCL F<.COM> files, if
e41182b5
GS
980you are so inclined. For example:
981
982 $ write sys$output "Hello from DCL!"
983 $ if p1 .eqs. ""
984 $ then perl -x 'f$environment("PROCEDURE")
985 $ else perl -x - 'p1 'p2 'p3 'p4 'p5 'p6 'p7 'p8
986 $ deck/dollars="__END__"
987 #!/usr/bin/perl
988
989 print "Hello from Perl!\n";
990
991 __END__
992 $ endif
993
994Do take care with C<$ ASSIGN/nolog/user SYS$COMMAND: SYS$INPUT> if your
c47ff5f1 995perl-in-DCL script expects to do things like C<< $read = <STDIN>; >>.
e41182b5
GS
996
997Filenames are in the format "name.extension;version". The maximum
998length for filenames is 39 characters, and the maximum length for
999extensions is also 39 characters. Version is a number from 1 to
100032767. Valid characters are C</[A-Z0-9$_-]/>.
1001
b7df3edc 1002VMS's RMS filesystem is case-insensitive and does not preserve case.
e41182b5 1003C<readdir> returns lowercased filenames, but specifying a file for
b7df3edc 1004opening remains case-insensitive. Files without extensions have a
e41182b5 1005trailing period on them, so doing a C<readdir> with a file named F<A.;5>
0a47030a
GS
1006will return F<a.> (though that file could be opened with
1007C<open(FH, 'A')>).
e41182b5 1008
f34d0673 1009RMS had an eight level limit on directory depths from any rooted logical
dd9f0070
CN
1010(allowing 16 levels overall) prior to VMS 7.2. Hence
1011C<PERL_ROOT:[LIB.2.3.4.5.6.7.8]> is a valid directory specification but
1012C<PERL_ROOT:[LIB.2.3.4.5.6.7.8.9]> is not. F<Makefile.PL> authors might
1013have to take this into account, but at least they can refer to the former
f34d0673 1014as C</PERL_ROOT/lib/2/3/4/5/6/7/8/>.
e41182b5 1015
6ab3f9cb 1016The VMS::Filespec module, which gets installed as part of the build
0a47030a
GS
1017process on VMS, is a pure Perl module that can easily be installed on
1018non-VMS platforms and can be helpful for conversions to and from RMS
1019native formats.
e41182b5 1020
5e12dbfa
PP
1021What C<\n> represents depends on the type of file opened. It usually
1022represents C<\012> but it could also be C<\015>, C<\012>, C<\015\012>,
1023C<\000>, C<\040>, or nothing depending on the file organiztion and
1024record format. The VMS::Stdio module provides access to the
1025special fopen() requirements of files with unusual attributes on VMS.
e41182b5
GS
1026
1027TCP/IP stacks are optional on VMS, so socket routines might not be
1028implemented. UDP sockets may not be supported.
1029
1030The value of C<$^O> on OpenVMS is "VMS". To determine the architecture
1031that you are running on without resorting to loading all of C<%Config>
1032you can examine the content of the C<@INC> array like so:
1033
1034 if (grep(/VMS_AXP/, @INC)) {
1035 print "I'm on Alpha!\n";
6ab3f9cb 1036
e41182b5
GS
1037 } elsif (grep(/VMS_VAX/, @INC)) {
1038 print "I'm on VAX!\n";
6ab3f9cb 1039
e41182b5
GS
1040 } else {
1041 print "I'm not so sure about where $^O is...\n";
1042 }
1043
b7df3edc
GS
1044On VMS, perl determines the UTC offset from the C<SYS$TIMEZONE_DIFFERENTIAL>
1045logical name. Although the VMS epoch began at 17-NOV-1858 00:00:00.00,
6ab3f9cb 1046calls to C<localtime> are adjusted to count offsets from
b7df3edc 104701-JAN-1970 00:00:00.00, just like Unix.
6ab3f9cb 1048
e41182b5
GS
1049Also see:
1050
1051=over 4
1052
c997b287
GS
1053=item *
1054
1055F<README.vms> (installed as L<README_vms>), L<perlvms>
1056
1057=item *
1058
1059vmsperl list, majordomo@perl.org
e41182b5 1060
c997b287 1061(Put the words C<subscribe vmsperl> in message body.)
e41182b5 1062
c997b287 1063=item *
e41182b5 1064
c997b287 1065vmsperl on the web, http://www.sidhe.org/vmsperl/index.html
e41182b5
GS
1066
1067=back
1068
495c5fdc
GP
1069=head2 VOS
1070
9a997319
JH
1071Perl on VOS is discussed in F<README.vos> in the perl distribution
1072(installed as L<perlvos>). Perl on VOS can accept either VOS- or
1073Unix-style file specifications as in either of the following:
495c5fdc 1074
cc07ed0b
PG
1075 C<< $ perl -ne "print if /perl_setup/i" >system>notices >>
1076 C<< $ perl -ne "print if /perl_setup/i" /system/notices >>
495c5fdc
GP
1077
1078or even a mixture of both as in:
1079
cc07ed0b 1080 C<< $ perl -ne "print if /perl_setup/i" >system/notices >>
495c5fdc 1081
b7df3edc 1082Even though VOS allows the slash character to appear in object
495c5fdc
GP
1083names, because the VOS port of Perl interprets it as a pathname
1084delimiting character, VOS files, directories, or links whose names
1085contain a slash character cannot be processed. Such files must be
a3dfe201
GS
1086renamed before they can be processed by Perl. Note that VOS limits
1087file names to 32 or fewer characters.
495c5fdc 1088
cc07ed0b
PG
1089Perl on VOS can be built using two different compilers and two different
1090versions of the POSIX runtime. The recommended method for building full
1091Perl is with the GNU C compiler and the generally-available version of
1092VOS POSIX support. See F<README.vos> (installed as L<perlvos>) for
1093restrictions that apply when Perl is built using the VOS Standard C
1094compiler or the alpha version of VOS POSIX support.
495c5fdc
GP
1095
1096The value of C<$^O> on VOS is "VOS". To determine the architecture that
1097you are running on without resorting to loading all of C<%Config> you
c997b287 1098can examine the content of the @INC array like so:
495c5fdc 1099
24e8e380 1100 if ($^O =~ /VOS/) {
495c5fdc
GP
1101 print "I'm on a Stratus box!\n";
1102 } else {
1103 print "I'm not on a Stratus box!\n";
1104 die;
1105 }
1106
1107 if (grep(/860/, @INC)) {
1108 print "This box is a Stratus XA/R!\n";
6ab3f9cb 1109
495c5fdc 1110 } elsif (grep(/7100/, @INC)) {
24e8e380 1111 print "This box is a Stratus HP 7100 or 8xxx!\n";
6ab3f9cb 1112
495c5fdc 1113 } elsif (grep(/8000/, @INC)) {
24e8e380 1114 print "This box is a Stratus HP 8xxx!\n";
6ab3f9cb 1115
495c5fdc 1116 } else {
24e8e380 1117 print "This box is a Stratus 68K!\n";
495c5fdc
GP
1118 }
1119
1120Also see:
1121
1122=over 4
1123
c997b287 1124=item *
495c5fdc 1125
cc07ed0b 1126F<README.vos> (installed as L<perlvos>)
c997b287
GS
1127
1128=item *
1129
1130The VOS mailing list.
495c5fdc
GP
1131
1132There is no specific mailing list for Perl on VOS. You can post
1133comments to the comp.sys.stratus newsgroup, or subscribe to the general
cc07ed0b 1134Stratus mailing list. Send a letter with "subscribe Info-Stratus" in
495c5fdc
GP
1135the message body to majordomo@list.stratagy.com.
1136
c997b287
GS
1137=item *
1138
cc07ed0b 1139VOS Perl on the web at http://ftp.stratus.com/pub/vos/posix/posix.html
495c5fdc
GP
1140
1141=back
1142
e41182b5
GS
1143=head2 EBCDIC Platforms
1144
1145Recent versions of Perl have been ported to platforms such as OS/400 on
d1e3b762
GS
1146AS/400 minicomputers as well as OS/390, VM/ESA, and BS2000 for S/390
1147Mainframes. Such computers use EBCDIC character sets internally (usually
0cc436d0
GS
1148Character Code Set ID 0037 for OS/400 and either 1047 or POSIX-BC for S/390
1149systems). On the mainframe perl currently works under the "Unix system
1150services for OS/390" (formerly known as OpenEdition), VM/ESA OpenEdition, or
1151the BS200 POSIX-BC system (BS2000 is supported in perl 5.6 and greater).
c997b287 1152See L<perlos390> for details.
e41182b5 1153
7c5ffed3
JH
1154As of R2.5 of USS for OS/390 and Version 2.3 of VM/ESA these Unix
1155sub-systems do not support the C<#!> shebang trick for script invocation.
1156Hence, on OS/390 and VM/ESA perl scripts can be executed with a header
1157similar to the following simple script:
e41182b5
GS
1158
1159 : # use perl
1160 eval 'exec /usr/local/bin/perl -S $0 ${1+"$@"}'
1161 if 0;
1162 #!/usr/local/bin/perl # just a comment really
1163
1164 print "Hello from perl!\n";
1165
d1e3b762
GS
1166OS/390 will support the C<#!> shebang trick in release 2.8 and beyond.
1167Calls to C<system> and backticks can use POSIX shell syntax on all
1168S/390 systems.
1169
b7df3edc 1170On the AS/400, if PERL5 is in your library list, you may need
6ab3f9cb
GS
1171to wrap your perl scripts in a CL procedure to invoke them like so:
1172
1173 BEGIN
1174 CALL PGM(PERL5/PERL) PARM('/QOpenSys/hello.pl')
1175 ENDPGM
1176
1177This will invoke the perl script F<hello.pl> in the root of the
1178QOpenSys file system. On the AS/400 calls to C<system> or backticks
1179must use CL syntax.
1180
e41182b5 1181On these platforms, bear in mind that the EBCDIC character set may have
0a47030a
GS
1182an effect on what happens with some perl functions (such as C<chr>,
1183C<pack>, C<print>, C<printf>, C<ord>, C<sort>, C<sprintf>, C<unpack>), as
1184well as bit-fiddling with ASCII constants using operators like C<^>, C<&>
1185and C<|>, not to mention dealing with socket interfaces to ASCII computers
6ab3f9cb 1186(see L<"Newlines">).
e41182b5 1187
b7df3edc
GS
1188Fortunately, most web servers for the mainframe will correctly
1189translate the C<\n> in the following statement to its ASCII equivalent
1190(C<\r> is the same under both Unix and OS/390 & VM/ESA):
e41182b5
GS
1191
1192 print "Content-type: text/html\r\n\r\n";
1193
d1e3b762 1194The values of C<$^O> on some of these platforms includes:
e41182b5 1195
d1e3b762
GS
1196 uname $^O $Config{'archname'}
1197 --------------------------------------------
1198 OS/390 os390 os390
1199 OS400 os400 os400
1200 POSIX-BC posix-bc BS2000-posix-bc
1201 VM/ESA vmesa vmesa
3c075c7d 1202
e41182b5
GS
1203Some simple tricks for determining if you are running on an EBCDIC
1204platform could include any of the following (perhaps all):
1205
1206 if ("\t" eq "\05") { print "EBCDIC may be spoken here!\n"; }
1207
1208 if (ord('A') == 193) { print "EBCDIC may be spoken here!\n"; }
1209
1210 if (chr(169) eq 'z') { print "EBCDIC may be spoken here!\n"; }
1211
b7df3edc 1212One thing you may not want to rely on is the EBCDIC encoding
0a47030a
GS
1213of punctuation characters since these may differ from code page to code
1214page (and once your module or script is rumoured to work with EBCDIC,
1215folks will want it to work with all EBCDIC character sets).
e41182b5
GS
1216
1217Also see:
1218
1219=over 4
1220
c997b287
GS
1221=item *
1222
1223*
d1e3b762 1224
dc5c060f 1225L<perlos390>, F<README.os390>, F<perlbs2000>, F<README.vmesa>,
bb462878 1226L<perlebcdic>.
c997b287
GS
1227
1228=item *
e41182b5
GS
1229
1230The perl-mvs@perl.org list is for discussion of porting issues as well as
1231general usage issues for all EBCDIC Perls. Send a message body of
1232"subscribe perl-mvs" to majordomo@perl.org.
1233
c997b287
GS
1234=item *
1235
1236AS/400 Perl information at
b1866b2d 1237http://as400.rochester.ibm.com/
d1e3b762 1238as well as on CPAN in the F<ports/> directory.
e41182b5
GS
1239
1240=back
1241
b8099c3d
CN
1242=head2 Acorn RISC OS
1243
b7df3edc
GS
1244Because Acorns use ASCII with newlines (C<\n>) in text files as C<\012> like
1245Unix, and because Unix filename emulation is turned on by default,
1246most simple scripts will probably work "out of the box". The native
6ab3f9cb 1247filesystem is modular, and individual filesystems are free to be
0a47030a 1248case-sensitive or insensitive, and are usually case-preserving. Some
b7df3edc 1249native filesystems have name length limits, which file and directory
6ab3f9cb
GS
1250names are silently truncated to fit. Scripts should be aware that the
1251standard filesystem currently has a name length limit of B<10>
1252characters, with up to 77 items in a directory, but other filesystems
0a47030a 1253may not impose such limitations.
b8099c3d
CN
1254
1255Native filenames are of the form
1256
6ab3f9cb 1257 Filesystem#Special_Field::DiskName.$.Directory.Directory.File
dd9f0070 1258
b8099c3d
CN
1259where
1260
1261 Special_Field is not usually present, but may contain . and $ .
1262 Filesystem =~ m|[A-Za-z0-9_]|
1263 DsicName =~ m|[A-Za-z0-9_/]|
1264 $ represents the root directory
1265 . is the path separator
1266 @ is the current directory (per filesystem but machine global)
1267 ^ is the parent directory
1268 Directory and File =~ m|[^\0- "\.\$\%\&:\@\\^\|\177]+|
1269
1270The default filename translation is roughly C<tr|/.|./|;>
1271
6ab3f9cb 1272Note that C<"ADFS::HardDisk.$.File" ne 'ADFS::HardDisk.$.File'> and that
0a47030a
GS
1273the second stage of C<$> interpolation in regular expressions will fall
1274foul of the C<$.> if scripts are not careful.
1275
1276Logical paths specified by system variables containing comma-separated
b7df3edc 1277search lists are also allowed; hence C<System:Modules> is a valid
0a47030a 1278filename, and the filesystem will prefix C<Modules> with each section of
6ab3f9cb 1279C<System$Path> until a name is made that points to an object on disk.
b7df3edc 1280Writing to a new file C<System:Modules> would be allowed only if
0a47030a
GS
1281C<System$Path> contains a single item list. The filesystem will also
1282expand system variables in filenames if enclosed in angle brackets, so
c47ff5f1 1283C<< <System$Dir>.Modules >> would look for the file
0a47030a 1284S<C<$ENV{'System$Dir'} . 'Modules'>>. The obvious implication of this is
c47ff5f1 1285that B<fully qualified filenames can start with C<< <> >>> and should
0a47030a 1286be protected when C<open> is used for input.
b8099c3d
CN
1287
1288Because C<.> was in use as a directory separator and filenames could not
1289be assumed to be unique after 10 characters, Acorn implemented the C
1290compiler to strip the trailing C<.c> C<.h> C<.s> and C<.o> suffix from
1291filenames specified in source code and store the respective files in
b7df3edc 1292subdirectories named after the suffix. Hence files are translated:
b8099c3d
CN
1293
1294 foo.h h.foo
1295 C:foo.h C:h.foo (logical path variable)
1296 sys/os.h sys.h.os (C compiler groks Unix-speak)
1297 10charname.c c.10charname
1298 10charname.o o.10charname
1299 11charname_.c c.11charname (assuming filesystem truncates at 10)
1300
1301The Unix emulation library's translation of filenames to native assumes
b7df3edc
GS
1302that this sort of translation is required, and it allows a user-defined list
1303of known suffixes that it will transpose in this fashion. This may
1304seem transparent, but consider that with these rules C<foo/bar/baz.h>
0a47030a
GS
1305and C<foo/bar/h/baz> both map to C<foo.bar.h.baz>, and that C<readdir> and
1306C<glob> cannot and do not attempt to emulate the reverse mapping. Other
6ab3f9cb 1307C<.>'s in filenames are translated to C</>.
0a47030a 1308
b7df3edc 1309As implied above, the environment accessed through C<%ENV> is global, and
0a47030a 1310the convention is that program specific environment variables are of the
6ab3f9cb
GS
1311form C<Program$Name>. Each filesystem maintains a current directory,
1312and the current filesystem's current directory is the B<global> current
b7df3edc
GS
1313directory. Consequently, sociable programs don't change the current
1314directory but rely on full pathnames, and programs (and Makefiles) cannot
0a47030a
GS
1315assume that they can spawn a child process which can change the current
1316directory without affecting its parent (and everyone else for that
1317matter).
1318
b7df3edc
GS
1319Because native operating system filehandles are global and are currently
1320allocated down from 255, with 0 being a reserved value, the Unix emulation
0a47030a
GS
1321library emulates Unix filehandles. Consequently, you can't rely on
1322passing C<STDIN>, C<STDOUT>, or C<STDERR> to your children.
1323
1324The desire of users to express filenames of the form
c47ff5f1 1325C<< <Foo$Dir>.Bar >> on the command line unquoted causes problems,
0a47030a 1326too: C<``> command output capture has to perform a guessing game. It
c47ff5f1 1327assumes that a string C<< <[^<>]+\$[^<>]> >> is a
0a47030a 1328reference to an environment variable, whereas anything else involving
c47ff5f1 1329C<< < >> or C<< > >> is redirection, and generally manages to be 99%
0a47030a
GS
1330right. Of course, the problem remains that scripts cannot rely on any
1331Unix tools being available, or that any tools found have Unix-like command
1332line arguments.
1333
b7df3edc
GS
1334Extensions and XS are, in theory, buildable by anyone using free
1335tools. In practice, many don't, as users of the Acorn platform are
1336used to binary distributions. MakeMaker does run, but no available
1337make currently copes with MakeMaker's makefiles; even if and when
1338this should be fixed, the lack of a Unix-like shell will cause
1339problems with makefile rules, especially lines of the form C<cd
1340sdbm && make all>, and anything using quoting.
b8099c3d
CN
1341
1342"S<RISC OS>" is the proper name for the operating system, but the value
1343in C<$^O> is "riscos" (because we don't like shouting).
1344
e41182b5
GS
1345=head2 Other perls
1346
b7df3edc
GS
1347Perl has been ported to many platforms that do not fit into any of
1348the categories listed above. Some, such as AmigaOS, Atari MiNT,
1349BeOS, HP MPE/iX, QNX, Plan 9, and VOS, have been well-integrated
1350into the standard Perl source code kit. You may need to see the
1351F<ports/> directory on CPAN for information, and possibly binaries,
1352for the likes of: aos, Atari ST, lynxos, riscos, Novell Netware,
1353Tandem Guardian, I<etc.> (Yes, we know that some of these OSes may
1354fall under the Unix category, but we are not a standards body.)
e41182b5 1355
d1e3b762
GS
1356Some approximate operating system names and their C<$^O> values
1357in the "OTHER" category include:
1358
1359 OS $^O $Config{'archname'}
1360 ------------------------------------------
1361 Amiga DOS amigaos m68k-amigos
1362 MPE/iX mpeix PA-RISC1.1
1363
e41182b5
GS
1364See also:
1365
1366=over 4
1367
c997b287
GS
1368=item *
1369
1370Amiga, F<README.amiga> (installed as L<perlamiga>).
1371
1372=item *
d1e3b762 1373
c997b287
GS
1374Atari, F<README.mint> and Guido Flohr's web page
1375http://stud.uni-sb.de/~gufl0000/
e41182b5 1376
c997b287 1377=item *
d1e3b762 1378
c997b287 1379Be OS, F<README.beos>
e41182b5 1380
c997b287
GS
1381=item *
1382
1383HP 300 MPE/iX, F<README.mpeix> and Mark Bixby's web page
34aaaa84 1384http://www.bixby.org/mark/perlix.html
c997b287
GS
1385
1386=item *
e41182b5 1387
6ab3f9cb 1388A free perl5-based PERL.NLM for Novell Netware is available in
c997b287 1389precompiled binary and source code form from http://www.novell.com/
6ab3f9cb 1390as well as from CPAN.
e41182b5 1391
13a2d996 1392=item *
c997b287
GS
1393
1394Plan 9, F<README.plan9>
d1e3b762 1395
e41182b5
GS
1396=back
1397
e41182b5
GS
1398=head1 FUNCTION IMPLEMENTATIONS
1399
b7df3edc
GS
1400Listed below are functions that are either completely unimplemented
1401or else have been implemented differently on various platforms.
1402Following each description will be, in parentheses, a list of
1403platforms that the description applies to.
e41182b5 1404
b7df3edc
GS
1405The list may well be incomplete, or even wrong in some places. When
1406in doubt, consult the platform-specific README files in the Perl
1407source distribution, and any other documentation resources accompanying
1408a given port.
e41182b5 1409
0a47030a 1410Be aware, moreover, that even among Unix-ish systems there are variations.
e41182b5 1411
b7df3edc
GS
1412For many functions, you can also query C<%Config>, exported by
1413default from the Config module. For example, to check whether the
1414platform has the C<lstat> call, check C<$Config{d_lstat}>. See
1415L<Config> for a full description of available variables.
e41182b5
GS
1416
1417=head2 Alphabetical Listing of Perl Functions
1418
1419=over 8
1420
1421=item -X FILEHANDLE
1422
1423=item -X EXPR
1424
1425=item -X
1426
b7df3edc 1427C<-r>, C<-w>, and C<-x> have a limited meaning only; directories
e41182b5 1428and applications are executable, and there are no uid/gid
b7df3edc 1429considerations. C<-o> is not supported. (S<Mac OS>)
e41182b5 1430
b7df3edc
GS
1431C<-r>, C<-w>, C<-x>, and C<-o> tell whether the file is accessible,
1432which may not reflect UIC-based file protections. (VMS)
e41182b5 1433
b8099c3d
CN
1434C<-s> returns the size of the data fork, not the total size of data fork
1435plus resource fork. (S<Mac OS>).
1436
1437C<-s> by name on an open file will return the space reserved on disk,
1438rather than the current extent. C<-s> on an open filehandle returns the
b7df3edc 1439current size. (S<RISC OS>)
b8099c3d 1440
e41182b5 1441C<-R>, C<-W>, C<-X>, C<-O> are indistinguishable from C<-r>, C<-w>,
b8099c3d 1442C<-x>, C<-o>. (S<Mac OS>, Win32, VMS, S<RISC OS>)
e41182b5
GS
1443
1444C<-b>, C<-c>, C<-k>, C<-g>, C<-p>, C<-u>, C<-A> are not implemented.
1445(S<Mac OS>)
1446
1447C<-g>, C<-k>, C<-l>, C<-p>, C<-u>, C<-A> are not particularly meaningful.
b8099c3d 1448(Win32, VMS, S<RISC OS>)
e41182b5
GS
1449
1450C<-d> is true if passed a device spec without an explicit directory.
1451(VMS)
1452
1453C<-T> and C<-B> are implemented, but might misclassify Mac text files
0a47030a 1454with foreign characters; this is the case will all platforms, but may
b7df3edc 1455affect S<Mac OS> often. (S<Mac OS>)
e41182b5
GS
1456
1457C<-x> (or C<-X>) determine if a file ends in one of the executable
b7df3edc 1458suffixes. C<-S> is meaningless. (Win32)
e41182b5 1459
b8099c3d
CN
1460C<-x> (or C<-X>) determine if a file has an executable file type.
1461(S<RISC OS>)
1462
63f87e49
GS
1463=item alarm SECONDS
1464
1465=item alarm
1466
1467Not implemented. (Win32)
1468
e41182b5
GS
1469=item binmode FILEHANDLE
1470
b7df3edc 1471Meaningless. (S<Mac OS>, S<RISC OS>)
e41182b5
GS
1472
1473Reopens file and restores pointer; if function fails, underlying
1474filehandle may be closed, or pointer may be in a different position.
1475(VMS)
1476
1477The value returned by C<tell> may be affected after the call, and
1478the filehandle may be flushed. (Win32)
1479
1480=item chmod LIST
1481
b7df3edc 1482Only limited meaning. Disabling/enabling write permission is mapped to
e41182b5
GS
1483locking/unlocking the file. (S<Mac OS>)
1484
1485Only good for changing "owner" read-write access, "group", and "other"
1486bits are meaningless. (Win32)
1487
b8099c3d
CN
1488Only good for changing "owner" and "other" read-write access. (S<RISC OS>)
1489
495c5fdc
GP
1490Access permissions are mapped onto VOS access-control list changes. (VOS)
1491
4e51f8e4 1492The actual permissions set depend on the value of the C<CYGWIN>
789f0d36 1493in the SYSTEM environment settings. (Cygwin)
4e51f8e4 1494
e41182b5
GS
1495=item chown LIST
1496
495c5fdc 1497Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>, VOS)
e41182b5
GS
1498
1499Does nothing, but won't fail. (Win32)
1500
1501=item chroot FILENAME
1502
1503=item chroot
1504
7c5ffed3 1505Not implemented. (S<Mac OS>, Win32, VMS, Plan9, S<RISC OS>, VOS, VM/ESA)
e41182b5
GS
1506
1507=item crypt PLAINTEXT,SALT
1508
1509May not be available if library or source was not provided when building
b8099c3d 1510perl. (Win32)
e41182b5 1511
495c5fdc
GP
1512Not implemented. (VOS)
1513
e41182b5
GS
1514=item dbmclose HASH
1515
495c5fdc 1516Not implemented. (VMS, Plan9, VOS)
e41182b5
GS
1517
1518=item dbmopen HASH,DBNAME,MODE
1519
495c5fdc 1520Not implemented. (VMS, Plan9, VOS)
e41182b5
GS
1521
1522=item dump LABEL
1523
b8099c3d 1524Not useful. (S<Mac OS>, S<RISC OS>)
e41182b5
GS
1525
1526Not implemented. (Win32)
1527
b8099c3d 1528Invokes VMS debugger. (VMS)
e41182b5
GS
1529
1530=item exec LIST
1531
1532Not implemented. (S<Mac OS>)
1533
7c5ffed3 1534Implemented via Spawn. (VM/ESA)
3c075c7d 1535
0f897271
GS
1536Does not automatically flush output handles on some platforms.
1537(SunOS, Solaris, HP-UX)
1538
fe12c0e8
MS
1539=item exit EXPR
1540
1541=item exit
1542
1543Emulates UNIX exit() (which considers C<exit 1> to indicate an error) by
1544mapping the C<1> to SS$_ABORT (C<44>). This behavior may be overridden
1545with the pragma C<use vmsish 'exit'>. As with the CRTL's exit()
1546function, C<exit 0> is also mapped to an exit status of SS$_NORMAL
1547(C<1>); this mapping cannot be overridden. Any other argument to exit()
1548is used directly as Perl's exit status. (VMS)
1549
e41182b5
GS
1550=item fcntl FILEHANDLE,FUNCTION,SCALAR
1551
1552Not implemented. (Win32, VMS)
1553
1554=item flock FILEHANDLE,OPERATION
1555
495c5fdc 1556Not implemented (S<Mac OS>, VMS, S<RISC OS>, VOS).
e41182b5
GS
1557
1558Available only on Windows NT (not on Windows 95). (Win32)
1559
1560=item fork
1561
0f897271
GS
1562Not implemented. (S<Mac OS>, AmigaOS, S<RISC OS>, VOS, VM/ESA)
1563
1564Emulated using multiple interpreters. See L<perlfork>. (Win32)
1565
1566Does not automatically flush output handles on some platforms.
1567(SunOS, Solaris, HP-UX)
e41182b5
GS
1568
1569=item getlogin
1570
b8099c3d 1571Not implemented. (S<Mac OS>, S<RISC OS>)
e41182b5
GS
1572
1573=item getpgrp PID
1574
495c5fdc 1575Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS)
e41182b5
GS
1576
1577=item getppid
1578
b8099c3d 1579Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)
e41182b5
GS
1580
1581=item getpriority WHICH,WHO
1582
7c5ffed3 1583Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS, VM/ESA)
e41182b5
GS
1584
1585=item getpwnam NAME
1586
1587Not implemented. (S<Mac OS>, Win32)
1588
b8099c3d
CN
1589Not useful. (S<RISC OS>)
1590
e41182b5
GS
1591=item getgrnam NAME
1592
b8099c3d 1593Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)
e41182b5
GS
1594
1595=item getnetbyname NAME
1596
1597Not implemented. (S<Mac OS>, Win32, Plan9)
1598
1599=item getpwuid UID
1600
1601Not implemented. (S<Mac OS>, Win32)
1602
b8099c3d
CN
1603Not useful. (S<RISC OS>)
1604
e41182b5
GS
1605=item getgrgid GID
1606
b8099c3d 1607Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)
e41182b5
GS
1608
1609=item getnetbyaddr ADDR,ADDRTYPE
1610
1611Not implemented. (S<Mac OS>, Win32, Plan9)
1612
1613=item getprotobynumber NUMBER
1614
1615Not implemented. (S<Mac OS>)
1616
1617=item getservbyport PORT,PROTO
1618
1619Not implemented. (S<Mac OS>)
1620
1621=item getpwent
1622
7c5ffed3 1623Not implemented. (S<Mac OS>, Win32, VM/ESA)
e41182b5
GS
1624
1625=item getgrent
1626
7c5ffed3 1627Not implemented. (S<Mac OS>, Win32, VMS, VM/ESA)
e41182b5
GS
1628
1629=item gethostent
1630
1631Not implemented. (S<Mac OS>, Win32)
1632
1633=item getnetent
1634
1635Not implemented. (S<Mac OS>, Win32, Plan9)
1636
1637=item getprotoent
1638
1639Not implemented. (S<Mac OS>, Win32, Plan9)
1640
1641=item getservent
1642
1643Not implemented. (Win32, Plan9)
1644
e41182b5
GS
1645=item sethostent STAYOPEN
1646
b8099c3d 1647Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)
e41182b5
GS
1648
1649=item setnetent STAYOPEN
1650
b8099c3d 1651Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)
e41182b5
GS
1652
1653=item setprotoent STAYOPEN
1654
b8099c3d 1655Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)
e41182b5
GS
1656
1657=item setservent STAYOPEN
1658
b8099c3d 1659Not implemented. (Plan9, Win32, S<RISC OS>)
e41182b5
GS
1660
1661=item endpwent
1662
a3dfe201 1663Not implemented. (S<Mac OS>, MPE/iX, VM/ESA, Win32)
e41182b5
GS
1664
1665=item endgrent
1666
a3dfe201 1667Not implemented. (S<Mac OS>, MPE/iX, S<RISC OS>, VM/ESA, VMS, Win32)
e41182b5
GS
1668
1669=item endhostent
1670
1671Not implemented. (S<Mac OS>, Win32)
1672
1673=item endnetent
1674
1675Not implemented. (S<Mac OS>, Win32, Plan9)
1676
1677=item endprotoent
1678
1679Not implemented. (S<Mac OS>, Win32, Plan9)
1680
1681=item endservent
1682
1683Not implemented. (Plan9, Win32)
1684
1685=item getsockopt SOCKET,LEVEL,OPTNAME
1686
97c10e77 1687Not implemented. (Plan9)
e41182b5
GS
1688
1689=item glob EXPR
1690
1691=item glob
1692
63f87e49
GS
1693This operator is implemented via the File::Glob extension on most
1694platforms. See L<File::Glob> for portability information.
b8099c3d 1695
e41182b5
GS
1696=item ioctl FILEHANDLE,FUNCTION,SCALAR
1697
1698Not implemented. (VMS)
1699
1700Available only for socket handles, and it does what the ioctlsocket() call
1701in the Winsock API does. (Win32)
1702
b8099c3d
CN
1703Available only for socket handles. (S<RISC OS>)
1704
b350dd2f 1705=item kill SIGNAL, LIST
e41182b5 1706
862b5365
JH
1707C<kill(0, LIST)> is implemented for the sake of taint checking;
1708use with other signals is unimplemented. (S<Mac OS>)
1709
1710Not implemented, hence not useful for taint checking. (S<RISC OS>)
e41182b5 1711
63f87e49
GS
1712C<kill()> doesn't have the semantics of C<raise()>, i.e. it doesn't send
1713a signal to the identified process like it does on Unix platforms.
1714Instead C<kill($sig, $pid)> terminates the process identified by $pid,
1715and makes it exit immediately with exit status $sig. As in Unix, if
1716$sig is 0 and the specified process exists, it returns true without
1717actually terminating it. (Win32)
e41182b5
GS
1718
1719=item link OLDFILE,NEWFILE
1720
a3dfe201 1721Not implemented. (S<Mac OS>, MPE/iX, VMS, S<RISC OS>)
e41182b5 1722
433acd8a
JH
1723Link count not updated because hard links are not quite that hard
1724(They are sort of half-way between hard and soft links). (AmigaOS)
1725
a3dfe201
GS
1726Hard links are implemented on Win32 (Windows NT and Windows 2000)
1727under NTFS only.
1728
e41182b5
GS
1729=item lstat FILEHANDLE
1730
1731=item lstat EXPR
1732
1733=item lstat
1734
b8099c3d 1735Not implemented. (VMS, S<RISC OS>)
e41182b5 1736
63f87e49 1737Return values (especially for device and inode) may be bogus. (Win32)
e41182b5
GS
1738
1739=item msgctl ID,CMD,ARG
1740
1741=item msgget KEY,FLAGS
1742
1743=item msgsnd ID,MSG,FLAGS
1744
1745=item msgrcv ID,VAR,SIZE,TYPE,FLAGS
1746
495c5fdc 1747Not implemented. (S<Mac OS>, Win32, VMS, Plan9, S<RISC OS>, VOS)
e41182b5
GS
1748
1749=item open FILEHANDLE,EXPR
1750
1751=item open FILEHANDLE
1752
b7df3edc 1753The C<|> variants are supported only if ToolServer is installed.
e41182b5
GS
1754(S<Mac OS>)
1755
c47ff5f1 1756open to C<|-> and C<-|> are unsupported. (S<Mac OS>, Win32, S<RISC OS>)
e41182b5 1757
0f897271
GS
1758Opening a process does not automatically flush output handles on some
1759platforms. (SunOS, Solaris, HP-UX)
1760
e41182b5
GS
1761=item pipe READHANDLE,WRITEHANDLE
1762
433acd8a
JH
1763Very limited functionality. (MiNT)
1764
e41182b5
GS
1765=item readlink EXPR
1766
1767=item readlink
1768
b8099c3d 1769Not implemented. (Win32, VMS, S<RISC OS>)
e41182b5
GS
1770
1771=item select RBITS,WBITS,EBITS,TIMEOUT
1772
689c5c24 1773Only implemented on sockets. (Win32, VMS)
e41182b5 1774
b8099c3d
CN
1775Only reliable on sockets. (S<RISC OS>)
1776
76e05f0b 1777Note that the C<select FILEHANDLE> form is generally portable.
63f87e49 1778
e41182b5
GS
1779=item semctl ID,SEMNUM,CMD,ARG
1780
1781=item semget KEY,NSEMS,FLAGS
1782
1783=item semop KEY,OPSTRING
1784
495c5fdc 1785Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS)
e41182b5 1786
a3dfe201
GS
1787=item setgrent
1788
74555b7a 1789Not implemented. (S<Mac OS>, MPE/iX, VMS, Win32, VMS, S<RISC OS>)
a3dfe201 1790
e41182b5
GS
1791=item setpgrp PID,PGRP
1792
495c5fdc 1793Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS)
e41182b5
GS
1794
1795=item setpriority WHICH,WHO,PRIORITY
1796
495c5fdc 1797Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS)
e41182b5 1798
a3dfe201
GS
1799=item setpwent
1800
74555b7a 1801Not implemented. (S<Mac OS>, MPE/iX, Win32, S<RISC OS>)
a3dfe201 1802
e41182b5
GS
1803=item setsockopt SOCKET,LEVEL,OPTNAME,OPTVAL
1804
97c10e77 1805Not implemented. (Plan9)
e41182b5
GS
1806
1807=item shmctl ID,CMD,ARG
1808
1809=item shmget KEY,SIZE,FLAGS
1810
1811=item shmread ID,VAR,POS,SIZE
1812
1813=item shmwrite ID,STRING,POS,SIZE
1814
495c5fdc 1815Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS)
e41182b5 1816
80cbd5ad
JH
1817=item sockatmark SOCKET
1818
1819A relatively recent addition to socket functions, may not
1820be implemented even in UNIX platforms.
1821
e41182b5
GS
1822=item socketpair SOCKET1,SOCKET2,DOMAIN,TYPE,PROTOCOL
1823
862b5365 1824Not implemented. (Win32, VMS, S<RISC OS>, VOS, VM/ESA)
e41182b5
GS
1825
1826=item stat FILEHANDLE
1827
1828=item stat EXPR
1829
1830=item stat
1831
d62e1b7f
JH
1832Platforms that do not have rdev, blksize, or blocks will return these
1833as '', so numeric comparison or manipulation of these fields may cause
1834'not numeric' warnings.
1835
e41182b5 1836mtime and atime are the same thing, and ctime is creation time instead of
3f1f789b
JH
1837inode change time. (S<Mac OS>).
1838
1839ctime not supported on UFS (S<Mac OS X>).
e41182b5 1840
95a3fe12
MS
1841ctime is creation time instead of inode change time (Win32).
1842
e41182b5
GS
1843device and inode are not meaningful. (Win32)
1844
1845device and inode are not necessarily reliable. (VMS)
1846
b8099c3d
CN
1847mtime, atime and ctime all return the last modification time. Device and
1848inode are not necessarily reliable. (S<RISC OS>)
1849
d62e1b7f
JH
1850dev, rdev, blksize, and blocks are not available. inode is not
1851meaningful and will differ between stat calls on the same file. (os2)
1852
73e9292c
JH
1853some versions of cygwin when doing a stat("foo") and if not finding it
1854may then attempt to stat("foo.exe") (Cygwin)
1855
e41182b5
GS
1856=item symlink OLDFILE,NEWFILE
1857
b8099c3d 1858Not implemented. (Win32, VMS, S<RISC OS>)
e41182b5
GS
1859
1860=item syscall LIST
1861
7c5ffed3 1862Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>, VOS, VM/ESA)
e41182b5 1863
f34d0673
GS
1864=item sysopen FILEHANDLE,FILENAME,MODE,PERMS
1865
dd9f0070 1866The traditional "0", "1", and "2" MODEs are implemented with different
322422de
GS
1867numeric values on some systems. The flags exported by C<Fcntl>
1868(O_RDONLY, O_WRONLY, O_RDWR) should work everywhere though. (S<Mac
7c5ffed3 1869OS>, OS/390, VM/ESA)
f34d0673 1870
e41182b5
GS
1871=item system LIST
1872
9d6eb86e 1873In general, do not assume the UNIX/POSIX semantics that you can shift
7717d0e7 1874C<$?> right by eight to get the exit value, or that C<$? & 127>
9d6eb86e
JH
1875would give you the number of the signal that terminated the program,
1876or that C<$? & 128> would test true if the program was terminated by a
1877coredump. Instead, use the POSIX W*() interfaces: for example, use
74555b7a
PP
1878WIFEXITED($?) and WEXITVALUE($?) to test for a normal exit and the exit
1879value, WIFSIGNALED($?) and WTERMSIG($?) for a signal exit and the
7717d0e7 1880signal. Core dumping is not a portable concept, so there's no portable
9d6eb86e
JH
1881way to test for that.
1882
e41182b5
GS
1883Only implemented if ToolServer is installed. (S<Mac OS>)
1884
1885As an optimization, may not call the command shell specified in
b7df3edc 1886C<$ENV{PERL5SHELL}>. C<system(1, @args)> spawns an external
e41182b5
GS
1887process and immediately returns its process designator, without
1888waiting for it to terminate. Return value may be used subsequently
63f87e49
GS
1889in C<wait> or C<waitpid>. Failure to spawn() a subprocess is indicated
1890by setting $? to "255 << 8". C<$?> is set in a way compatible with
1891Unix (i.e. the exitstatus of the subprocess is obtained by "$? >> 8",
1892as described in the documentation). (Win32)
e41182b5 1893
b8099c3d
CN
1894There is no shell to process metacharacters, and the native standard is
1895to pass a command line terminated by "\n" "\r" or "\0" to the spawned
c47ff5f1 1896program. Redirection such as C<< > foo >> is performed (if at all) by
b8099c3d
CN
1897the run time library of the spawned program. C<system> I<list> will call
1898the Unix emulation library's C<exec> emulation, which attempts to provide
1899emulation of the stdin, stdout, stderr in force in the parent, providing
1900the child program uses a compatible version of the emulation library.
1901I<scalar> will call the native command line direct and no such emulation
1902of a child Unix program will exists. Mileage B<will> vary. (S<RISC OS>)
1903
433acd8a
JH
1904Far from being POSIX compliant. Because there may be no underlying
1905/bin/sh tries to work around the problem by forking and execing the
9b63e9ec 1906first token in its argument string. Handles basic redirection
c47ff5f1 1907("<" or ">") on its own behalf. (MiNT)
433acd8a 1908
0f897271
GS
1909Does not automatically flush output handles on some platforms.
1910(SunOS, Solaris, HP-UX)
1911
9bc98430
CB
1912The return value is POSIX-like (shifted up by 8 bits), which only allows
1913room for a made-up value derived from the severity bits of the native
191432-bit condition code (unless overridden by C<use vmsish 'status'>).
1915For more details see L<perlvms/$?>. (VMS)
1916
e41182b5
GS
1917=item times
1918
1919Only the first entry returned is nonzero. (S<Mac OS>)
1920
63f87e49
GS
1921"cumulative" times will be bogus. On anything other than Windows NT
1922or Windows 2000, "system" time will be bogus, and "user" time is
1923actually the time returned by the clock() function in the C runtime
1924library. (Win32)
e41182b5 1925
b8099c3d
CN
1926Not useful. (S<RISC OS>)
1927
e41182b5
GS
1928=item truncate FILEHANDLE,LENGTH
1929
1930=item truncate EXPR,LENGTH
1931
6d738113 1932Not implemented. (Older versions of VMS)
e41182b5 1933
495c5fdc
GP
1934Truncation to zero-length only. (VOS)
1935
4cfdb94f 1936If a FILEHANDLE is supplied, it must be writable and opened in append
e71a7dc8 1937mode (i.e., use C<<< open(FH, '>>filename') >>>
4cfdb94f
GS
1938or C<sysopen(FH,...,O_APPEND|O_RDWR)>. If a filename is supplied, it
1939should not be held open elsewhere. (Win32)
1940
e41182b5
GS
1941=item umask EXPR
1942
1943=item umask
1944
1945Returns undef where unavailable, as of version 5.005.
1946
b7df3edc
GS
1947C<umask> works but the correct permissions are set only when the file
1948is finally closed. (AmigaOS)
433acd8a 1949
e41182b5
GS
1950=item utime LIST
1951
15c65113 1952Only the modification time is updated. (S<BeOS>, S<Mac OS>, VMS, S<RISC OS>)
e41182b5 1953
322422de
GS
1954May not behave as expected. Behavior depends on the C runtime
1955library's implementation of utime(), and the filesystem being
1956used. The FAT filesystem typically does not support an "access
1957time" field, and it may limit timestamps to a granularity of
1958two seconds. (Win32)
e41182b5
GS
1959
1960=item wait
1961
1962=item waitpid PID,FLAGS
1963
495c5fdc 1964Not implemented. (S<Mac OS>, VOS)
e41182b5
GS
1965
1966Can only be applied to process handles returned for processes spawned
a6f858fb 1967using C<system(1, ...)> or pseudo processes created with C<fork()>. (Win32)
e41182b5 1968
b8099c3d
CN
1969Not useful. (S<RISC OS>)
1970
e41182b5
GS
1971=back
1972
b8099c3d
CN
1973=head1 CHANGES
1974
1975=over 4
1976
fd46a41b
JH
1977=item v1.48, 02 February 2001
1978
1979Various updates from perl5-porters over the past year, supported
1980platforms update from Jarkko Hietaniemi.
1981
c997b287
GS
1982=item v1.47, 22 March 2000
1983
1984Various cleanups from Tom Christiansen, including migration of
1985long platform listings from L<perl>.
1986
56d7751a
GS
1987=item v1.46, 12 February 2000
1988
1989Updates for VOS and MPE/iX. (Peter Prymmer) Other small changes.
1990
0cc436d0
GS
1991=item v1.45, 20 December 1999
1992
1993Small changes from 5.005_63 distribution, more changes to EBCDIC info.
1994
d1e3b762
GS
1995=item v1.44, 19 July 1999
1996
1997A bunch of updates from Peter Prymmer for C<$^O> values,
1998endianness, File::Spec, VMS, BS2000, OS/400.
1999
b7df3edc
GS
2000=item v1.43, 24 May 1999
2001
2002Added a lot of cleaning up from Tom Christiansen.
2003
19799a22 2004=item v1.42, 22 May 1999
b7df3edc 2005
19799a22 2006Added notes about tests, sprintf/printf, and epoch offsets.
b7df3edc 2007
6ab3f9cb
GS
2008=item v1.41, 19 May 1999
2009
2010Lots more little changes to formatting and content.
2011
d1e3b762 2012Added a bunch of C<$^O> and related values
6ab3f9cb
GS
2013for various platforms; fixed mail and web addresses, and added
2014and changed miscellaneous notes. (Peter Prymmer)
2015
2016=item v1.40, 11 April 1999
2017
2018Miscellaneous changes.
2019
2020=item v1.39, 11 February 1999
2ee0eb3c
CN
2021
2022Changes from Jarkko and EMX URL fixes Michael Schwern. Additional
2023note about newlines added.
2024
9b63e9ec
CN
2025=item v1.38, 31 December 1998
2026
2027More changes from Jarkko.
2028
3c075c7d
CN
2029=item v1.37, 19 December 1998
2030
2031More minor changes. Merge two separate version 1.35 documents.
2032
2033=item v1.36, 9 September 1998
2034
2035Updated for Stratus VOS. Also known as version 1.35.
2036
2037=item v1.35, 13 August 1998
495c5fdc 2038
3c075c7d
CN
2039Integrate more minor changes, plus addition of new sections under
2040L<"ISSUES">: L<"Numbers endianness and Width">,
2041L<"Character sets and character encoding">,
2042L<"Internationalisation">.
495c5fdc 2043
3c075c7d 2044=item v1.33, 06 August 1998
0a47030a
GS
2045
2046Integrate more minor changes.
2047
3c075c7d 2048=item v1.32, 05 August 1998
dd9f0070
CN
2049
2050Integrate more minor changes.
2051
3c075c7d 2052=item v1.30, 03 August 1998
b8099c3d
CN
2053
2054Major update for RISC OS, other minor changes.
2055
3c075c7d 2056=item v1.23, 10 July 1998
b8099c3d
CN
2057
2058First public release with perl5.005.
2059
2060=back
e41182b5 2061
ba58ab26
JH
2062=head1 Supported Platforms
2063
9ca74005
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2064As of early 2001 (the Perl releases 5.6.1 and 5.7.1), the following
2065platforms are able to build Perl from the standard source code
a93751fa 2066distribution available at http://www.cpan.org/src/index.html
ba58ab26
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2067
2068 AIX
fd46a41b 2069 AmigaOS
b787fad4 2070 Darwin (Mac OS X)
fd46a41b 2071 DG/UX
ba58ab26 2072 DOS DJGPP 1)
fd46a41b 2073 DYNIX/ptx
2585f9a3 2074 EPOC R5
ba58ab26
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2075 FreeBSD
2076 HP-UX
2077 IRIX
2078 Linux
ba58ab26 2079 MachTen
fd46a41b
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2080 MacOS Classic 2)
2081 NonStop-UX
2082 ReliantUNIX (SINIX)
ba58ab26 2083 OpenBSD
fd46a41b 2084 OpenVMS (VMS)
ba58ab26 2085 OS/2
fd46a41b 2086 OS X
ba58ab26 2087 QNX
ba58ab26 2088 Solaris
fd46a41b 2089 Tru64 UNIX (DEC OSF/1, Digital UNIX)
ba58ab26
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2090 UNICOS
2091 UNICOS/mk
ba58ab26 2092 VOS
fd46a41b 2093 Win32/NT/2K 3)
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2094
2095 1) in DOS mode either the DOS or OS/2 ports can be used
fd46a41b
JH
2096 2) Mac OS Classic (pre-X) is almost 5.6.1-ready; building from
2097 the source does work with 5.6.1, but additional MacOS specific
862b5365
JH
2098 source code is needed for a complete build. See the web
2099 site http://dev.macperl.org/ for more information.
fd46a41b 2100 3) compilers: Borland, Cygwin, Mingw32 EGCS/GCC, VC++
ba58ab26 2101
9ca74005
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2102The following platforms worked for the previous releases (5.6.0 and 5.7.0),
2103but we did not manage to test these in time for the 5.7.1 release.
2104There is a very good chance that these will work fine with the 5.7.1.
ba58ab26 2105
ba58ab26
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2106 DomainOS
2107 Hurd
fd46a41b
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2108 LynxOS
2109 MinGW
2110 MPE/iX
2111 NetBSD
ba58ab26 2112 PowerMAX
fd46a41b 2113 SCO SV
ba58ab26 2114 SunOS
fd46a41b
JH
2115 SVR4
2116 Unixware
2117 Windows 3.1
2118 Windows 95
2119 Windows 98
2120 Windows Me
ba58ab26 2121
fd46a41b 2122The following platform worked for the 5.005_03 major release but not
9ca74005
JH
2123for 5.6.0. Standardization on UTF-8 as the internal string
2124representation in 5.6.0 and 5.6.1 introduced incompatibilities in this
2125EBCDIC platform. While Perl 5.7.1 will build on this platform some
fd46a41b 2126regression tests may fail and the C<use utf8;> pragma typically
9ca74005 2127introduces text handling errors.
ba58ab26 2128
fd46a41b 2129 OS/390 1)
ba58ab26 2130
fd46a41b 2131 1) previously known as MVS, about to become z/OS.
ba58ab26 2132
fd46a41b 2133Strongly related to the OS/390 platform by also being EBCDIC-based
ba58ab26
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2134mainframe platforms are the following platforms:
2135
fd46a41b 2136 POSIX-BC (BS2000)
ba58ab26
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2137 VM/ESA
2138
fd46a41b
JH
2139These are also expected to work, albeit with no UTF-8 support, under 5.6.1
2140for the same reasons as OS/390. Contact the mailing list perl-mvs@perl.org
2141for more details.
ba58ab26
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2142
2143The following platforms have been known to build Perl from source in
fd46a41b
JH
2144the past (5.005_03 and earlier), but we haven't been able to verify
2145their status for the current release, either because the
2146hardware/software platforms are rare or because we don't have an
2147active champion on these platforms--or both. They used to work,
2148though, so go ahead and try compiling them, and let perlbug@perl.org
2149of any trouble.
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2150
2151 3b1
fd46a41b
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2152 A/UX
2153 BeOS
2154 BSD/OS
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2155 ConvexOS
2156 CX/UX
2157 DC/OSx
2158 DDE SMES
2159 DOS EMX
2160 Dynix
2161 EP/IX
2162 ESIX
2163 FPS
2164 GENIX
2165 Greenhills
2166 ISC
2167 MachTen 68k
2168 MiNT
2169 MPC
2170 NEWS-OS
fd46a41b
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2171 NextSTEP
2172 OpenSTEP
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2173 Opus
2174 Plan 9
2175 PowerUX
2176 RISC/os
fd46a41b 2177 SCO ODT/OSR
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2178 Stellar
2179 SVR2
2180 TI1500
2181 TitanOS
fd46a41b 2182 Ultrix
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2183 Unisys Dynix
2184 Unixware
fd46a41b 2185 UTS
ba58ab26
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2186
2187Support for the following platform is planned for a future Perl release:
2188
2189 Netware
2190
2191The following platforms have their own source code distributions and
1577cd80 2192binaries available via http://www.cpan.org/ports/
ba58ab26
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2193
2194 Perl release
2195
ba58ab26 2196 Netware 5.003_07
fd46a41b 2197 OS/400 5.005_02
ba58ab26
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2198 Tandem Guardian 5.004
2199
2200The following platforms have only binaries available via
a93751fa 2201http://www.cpan.org/ports/index.html :
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2202
2203 Perl release
2204
2205 Acorn RISCOS 5.005_02
2206 AOS 5.002
2207 LynxOS 5.004_02
2208
2209Although we do suggest that you always build your own Perl from
2210the source code, both for maximal configurability and for security,
2211in case you are in a hurry you can check
a93751fa 2212http://www.cpan.org/ports/index.html for binary distributions.
ba58ab26 2213
c997b287
GS
2214=head1 SEE ALSO
2215
a83b6f46 2216L<perlaix>, L<perlapollo>, L<perlamiga>, L<perlbeos>, L<perlbs200>,
a1f19229 2217L<perlce>, L<perlcygwin>, L<perldgux>, L<perldos>, L<perlepoc>, L<perlebcdic>,
a83b6f46 2218L<perlhurd>, L<perlhpux>, L<perlmachten>, L<perlmacos>, L<perlmint>,
9038e305
JH
2219L<perlmpeix>, L<perlnetware>, L<perlos2>, L<perlos390>, L<perlplan9>,
2220L<perlqnx>, L<perlsolaris>, L<perltru64>, L<perlunicode>,
2221L<perlvmesa>, L<perlvms>, L<perlvos>, L<perlwin32>, and L<Win32>.
c997b287 2222
e41182b5
GS
2223=head1 AUTHORS / CONTRIBUTORS
2224
06e9666b 2225Abigail <abigail@foad.org>,
c47ff5f1
GS
2226Charles Bailey <bailey@newman.upenn.edu>,
2227Graham Barr <gbarr@pobox.com>,
2228Tom Christiansen <tchrist@perl.com>,
06e9666b 2229Nicholas Clark <nick@ccl4.org>,
c47ff5f1 2230Thomas Dorner <Thomas.Dorner@start.de>,
06e9666b
A
2231Andy Dougherty <doughera@lafayette.edu>,
2232Dominic Dunlop <domo@computer.org>,
2233Neale Ferguson <neale@vma.tabnsw.com.au>,
c47ff5f1
GS
2234David J. Fiander <davidf@mks.com>,
2235Paul Green <Paul_Green@stratus.com>,
06e9666b 2236M.J.T. Guy <mjtg@cam.ac.uk>,
61f30a5e 2237Jarkko Hietaniemi <jhi@iki.fi>,
c47ff5f1 2238Luther Huffman <lutherh@stratcom.com>,
06e9666b
A
2239Nick Ing-Simmons <nick@ing-simmons.net>,
2240Andreas J. KE<ouml>nig <a.koenig@mind.de>,
c47ff5f1
GS
2241Markus Laker <mlaker@contax.co.uk>,
2242Andrew M. Langmead <aml@world.std.com>,
2243Larry Moore <ljmoore@freespace.net>,
2244Paul Moore <Paul.Moore@uk.origin-it.com>,
2245Chris Nandor <pudge@pobox.com>,
1afc07ec 2246Matthias Neeracher <neeracher@mac.com>,
e71a7dc8 2247Philip Newton <pne@cpan.org>,
c47ff5f1
GS
2248Gary Ng <71564.1743@CompuServe.COM>,
2249Tom Phoenix <rootbeer@teleport.com>,
2250AndrE<eacute> Pirard <A.Pirard@ulg.ac.be>,
2251Peter Prymmer <pvhp@forte.com>,
2252Hugo van der Sanden <hv@crypt0.demon.co.uk>,
2253Gurusamy Sarathy <gsar@activestate.com>,
2254Paul J. Schinder <schinder@pobox.com>,
2255Michael G Schwern <schwern@pobox.com>,
06e9666b 2256Dan Sugalski <dan@sidhe.org>,
c47ff5f1 2257Nathan Torkington <gnat@frii.com>.
e41182b5 2258