S<[ B<-S> ]>
S<[ B<-x>[I<dir>] ]>
S<[ B<-i>[I<extension>] ]>
- S<[
B<-eE> I<'command'> ] [ B<--> ] [ I<programfile> ] [ I<argument> ]...>
+ S<[
[B<-e>|B<-E>] I<'command'> ] [ B<--> ] [ I<programfile> ] [ I<argument> ]...>
=head1 DESCRIPTION
The sequences "-*" and "- " are specifically ignored so that you could,
if you were so inclined, say
- #!/bin/sh -- # -*- perl -*- -p
- eval 'exec perl -wS $0 ${1+"$@"}'
- if $running_under_some_shell;
+ #!/bin/sh
+ #! -*-perl-*-
+ eval 'exec perl -x -wS $0 ${1+"$@"}'
+ if 0;
to let Perl see the B<-p> switch.
this means you can no longer tell the difference between an executable
Perl program and a Perl library file.
-=item Macintosh
-
-Under "Classic" MacOS, a perl program will have the appropriate Creator and
-Type, so that double-clicking them will invoke the MacPerl application.
-Under Mac OS X, clickable apps can be made from any C<#!> script using Wil
-Sanchez' DropScript utility: http://www.wsanchez.net/software/ .
-
=item VMS
Put
# MS-DOS, etc.
perl -e "print \"Hello world\n\""
- # Macintosh
- print "Hello world\n"
- (then Run "Myscript" or Shift-Command-R)
-
# VMS
perl -e "print ""Hello world\n"""
when nobody was looking, but just try to find documentation for its
quoting rules.
-Under the Macintosh, it depends which environment you are using. The MacPerl
-shell, or MPW, is much like Unix shells in its support for several
-quoting variants, except that it makes free use of the Macintosh's non-ASCII
-characters as control characters.
-
There is no general solution to all of this. It's just a mess.
=head2 Location of Perl
This feature was practically unused, however, and the command line
switch was therefore "recycled".)
+B<Note:> Since perl 5.10.1, if the -C option is used on the #! line, it
+must be specified on the command line as well, since the standard streams
+are already set up at this point in the execution of the perl interpreter.
+You can also use binmode() to set the encoding of an I/O stream.
+
=item B<-c>
X<-c>
16 o Method and overloading resolution
32 c String/numeric conversions
64 P Print profiling info, source file input state
- 128 m Memory allocation
+ 128 m Memory and SV allocation
256 f Format processing
512 r Regular expression parsing and execution
1024 x Syntax tree dump
8192 H Hash dump -- usurps values()
16384 X Scratchpad allocation
32768 D Cleaning up
- 65536 S Thread synchronization
131072 T Tokenising
262144 R Include reference counts of dumped variables (eg when using -Ds)
524288 J Do not s,t,P-debug (Jump over) opcodes within package DB
2097152 C Copy On Write
4194304 A Consistency checks on internal structures
8388608 q quiet - currently only suppresses the "EXECUTING" message
+ 16777216 M trace smart match resolution
+ 33554432 B dump suBroutine definitions, including special Blocks like BEGIN
All these flags require B<-DDEBUGGING> when you compile the Perl
executable (but see L<Devel::Peek>, L<re> which may change this).
lines printed. If a file named by an argument cannot be opened for
some reason, Perl warns you about it and moves on to the next file.
+Also note that C<< <> >> passes command line arguments to
+L<perlfunc/open>, which doesn't necessarily interpret them as file names.
+See L<perlop> for possible security implications.
+
Here is an efficient way to delete all files that haven't been modified for
at least a week:
ASCII text, such as in a mail message. Leading garbage will be
discarded until the first line that starts with #! and contains the
string "perl". Any meaningful switches on that line will be applied.
+
+All references to line numbers by the program (warnings, errors, ...)
+will treat the #! line as the first line.
+Thus a warning on the 2nd line of the program (which is on the 100th
+line in the file) will be reported as line 2, and not as line 100.
+This can be overridden by using the #line directive.
+(See L<perlsyn/"Plain-Old-Comments-(Not!)">)
+
If a directory name is specified, Perl will switch to that directory
before running the program. The B<-x> switch controls only the
disposal of leading garbage. The program must be terminated with
X<PERL5OPT>
Command-line options (switches). Switches in this variable are taken
-as if they were on every Perl command line. Only the B<-[CDIMUdmtw]>
+as if they were on every Perl command line. Only the B<-[CDIMUdmtwW]>
switches are allowed. When running taint checks (because the program
was running setuid or setgid, or the B<-T> switch was used), this
variable is ignored. If PERL5OPT begins with B<-T>, tainting will be
C<win32> layer which is expected to be enhanced and should eventually be
the default under Win32.
+The PERLIO environment variable is completely ignored when perl
+is run in taint mode.
+
=item PERLIO_DEBUG
X<PERLIO_DEBUG>
files before looking in the standard library and the current directory.
If PERL5LIB is defined, PERLLIB is not used.
+The PERLLIB environment variable is completely ignored when perl
+is run in taint mode.
+
=item PERL5DB
X<PERL5DB>
BEGIN { require 'perl5db.pl' }
+The PERL5DB environment variable only used when perl is started with
+a bare B<-d> switch.
+
=item PERL5DB_THREADED
X<PERL5DB_THREADED>
interfere with the proper functioning of other programs (which usually
look in COMSPEC to find a shell fit for interactive use).
+Before Perl 5.10.0 and 5.8.8, PERL5SHELL was not taint checked
+when running external commands. It is recommended that
+you explicitly set (or delete) C<$ENV{PERL5SHELL}> when running
+in taint mode under Windows.
+
=item PERL_ALLOW_NON_IFS_LSP (specific to the Win32 port)
X<PERL_ALLOW_NON_IFS_LSP>
https://perl5.git.perl.org / perl5.git / blobdiff