+ close(pd[0]); /* We write to pd[1] */
+ close(pu[1]); /* We read from pu[0] */
+ read(pu[0], buf, 1); /* Wait for parent to signal us we may continue */
+ close(pd[1]); /* Pipe pd is now fully closed! */
+ exit(0); /* Bye bye, thank you for playing! */
+}
+EOCP
+ set try
+ if eval $compile_ok; then
+ echo "$startsh" >mtry
+ echo "$run ./try >try.out 2>try.ret 4>try.err || exit 4" >>mtry
+ chmod +x mtry
+ ./mtry >/dev/null 2>&1
+ case $? in
+ 0) eagain=`$cat try.out`;;
+ 1) echo "Could not perform non-blocking setting!";;
+ 2) echo "I did a successful read() for something that was not there!";;
+ 3) echo "Hmm... non-blocking I/O does not seem to be working!";;
+ 4) echo "Could not find F_SETFL!";;
+ *) echo "Something terribly wrong happened during testing.";;
+ esac
+ rd_nodata=`$cat try.ret`
+ echo "A read() system call with no data present returns $rd_nodata."
+ case "$rd_nodata" in
+ 0|-1) ;;
+ *)
+ echo "(That's peculiar, fixing that to be -1.)"
+ rd_nodata=-1
+ ;;
+ esac
+ case "$eagain" in
+ '')
+ echo "Forcing errno EAGAIN on read() with no data available."
+ eagain=EAGAIN
+ ;;
+ *)
+ echo "Your read() sets errno to $eagain when no data is available."
+ ;;
+ esac
+ status=`$cat try.err`
+ case "$status" in
+ 0) echo "And it correctly returns 0 to signal EOF.";;
+ -1) echo "But it also returns -1 to signal EOF, so be careful!";;
+ *) echo "However, your read() returns '$status' on EOF??";;
+ esac
+ val="$define"
+ if test "$status" = "$rd_nodata"; then
+ echo "WARNING: you can't distinguish between EOF and no data!"
+ val="$undef"
+ fi
+ else
+ echo "I can't compile the test program--assuming errno EAGAIN will do."
+ eagain=EAGAIN
+ fi
+ set d_eofnblk
+ eval $setvar
+ ;;
+*)
+ echo "Using $hint value $eagain."
+ echo "Your read() returns $rd_nodata when no data is present."
+ case "$d_eofnblk" in
+ "$define") echo "And you can see EOF because read() returns 0.";;
+ "$undef") echo "But you can't see EOF status from read() returned value.";;
+ *)
+ echo "(Assuming you can't see EOF status from read anyway.)"
+ d_eofnblk=$undef
+ ;;
+ esac
+ ;;
+esac
+$rm -f try try.* .out core head.c mtry
+
+: see if _ptr and _cnt from stdio act std
+echo " "
+
+if $contains '_lbfsize' `./findhdr stdio.h` >/dev/null 2>&1 ; then
+ echo "(Looks like you have stdio.h from BSD.)"
+ case "$stdio_ptr" in
+ '') stdio_ptr='((fp)->_p)'
+ ptr_lval=$define
+ ;;
+ *) ptr_lval=$d_stdio_ptr_lval;;
+ esac
+ case "$stdio_cnt" in
+ '') stdio_cnt='((fp)->_r)'
+ cnt_lval=$define
+ ;;
+ *) cnt_lval=$d_stdio_cnt_lval;;
+ esac
+ case "$stdio_base" in
+ '') stdio_base='((fp)->_ub._base ? (fp)->_ub._base : (fp)->_bf._base)';;
+ esac
+ case "$stdio_bufsiz" in
+ '') stdio_bufsiz='((fp)->_ub._base ? (fp)->_ub._size : (fp)->_bf._size)';;
+ esac
+elif $contains '_IO_fpos_t' `./findhdr stdio.h` `./findhdr libio.h` >/dev/null 2>&1 ; then
+ echo "(Looks like you have stdio.h from Linux.)"
+ case "$stdio_ptr" in
+ '') stdio_ptr='((fp)->_IO_read_ptr)'
+ ptr_lval=$define
+ ;;
+ *) ptr_lval=$d_stdio_ptr_lval;;
+ esac
+ case "$stdio_cnt" in
+ '') stdio_cnt='((fp)->_IO_read_end - (fp)->_IO_read_ptr)'
+ cnt_lval=$undef
+ ;;
+ *) cnt_lval=$d_stdio_cnt_lval;;
+ esac
+ case "$stdio_base" in
+ '') stdio_base='((fp)->_IO_read_base)';;
+ esac
+ case "$stdio_bufsiz" in
+ '') stdio_bufsiz='((fp)->_IO_read_end - (fp)->_IO_read_base)';;
+ esac
+else
+ case "$stdio_ptr" in
+ '') stdio_ptr='((fp)->_ptr)'
+ ptr_lval=$define
+ ;;
+ *) ptr_lval=$d_stdio_ptr_lval;;
+ esac
+ case "$stdio_cnt" in
+ '') stdio_cnt='((fp)->_cnt)'
+ cnt_lval=$define
+ ;;
+ *) cnt_lval=$d_stdio_cnt_lval;;
+ esac
+ case "$stdio_base" in
+ '') stdio_base='((fp)->_base)';;
+ esac
+ case "$stdio_bufsiz" in
+ '') stdio_bufsiz='((fp)->_cnt + (fp)->_ptr - (fp)->_base)';;
+ esac
+fi
+
+: test whether _ptr and _cnt really work
+echo "Checking how std your stdio is..." >&4
+$cat >try.c <<EOP
+#include <stdio.h>
+#$i_stdlib I_STDLIB
+#ifdef I_STDLIB
+#include <stdlib.h>
+#endif
+#define FILE_ptr(fp) $stdio_ptr
+#define FILE_cnt(fp) $stdio_cnt
+int main() {
+ FILE *fp = fopen("try.c", "r");
+ char c = getc(fp);
+ if (
+ 18 <= FILE_cnt(fp) &&
+ strncmp(FILE_ptr(fp), "include <stdio.h>\n", 18) == 0
+ )
+ exit(0);
+ exit(1);
+}
+EOP
+val="$undef"
+set try
+if eval $compile && $to try.c; then
+ if $run ./try; then
+ echo "Your stdio acts pretty std."
+ val="$define"
+ else
+ echo "Your stdio isn't very std."
+ fi
+else
+ echo "Your stdio doesn't appear very std."
+fi
+$rm -f try.c try
+
+# glibc 2.2.90 and above apparently change stdio streams so Perl's
+# direct buffer manipulation no longer works. The Configure tests
+# should be changed to correctly detect this, but until then,
+# the following check should at least let perl compile and run.
+# (This quick fix should be updated before 5.8.1.)
+# To be defensive, reject all unknown versions, and all versions > 2.2.9.
+# A. Dougherty, June 3, 2002.
+case "$d_gnulibc" in
+$define)
+ case "$gnulibc_version" in
+ 2.[01]*) ;;
+ 2.2) ;;
+ 2.2.[0-9]) ;;
+ *) echo "But I will not snoop inside glibc $gnulibc_version stdio buffers."
+ val="$undef"
+ ;;
+ esac
+ ;;
+esac
+set d_stdstdio
+eval $setvar
+
+: Can _ptr be used as an lvalue?
+case "$d_stdstdio$ptr_lval" in
+$define$define) val=$define ;;
+*) val=$undef ;;
+esac
+set d_stdio_ptr_lval
+eval $setvar
+
+: Can _cnt be used as an lvalue?
+case "$d_stdstdio$cnt_lval" in
+$define$define) val=$define ;;
+*) val=$undef ;;
+esac
+set d_stdio_cnt_lval
+eval $setvar
+
+
+: test whether setting _ptr sets _cnt as a side effect
+d_stdio_ptr_lval_sets_cnt="$undef"
+d_stdio_ptr_lval_nochange_cnt="$undef"
+case "$d_stdio_ptr_lval$d_stdstdio" in
+$define$define)
+ echo "Checking to see what happens if we set the stdio ptr..." >&4
+$cat >try.c <<EOP
+#include <stdio.h>
+/* Can we scream? */
+/* Eat dust sed :-) */
+/* In the buffer space, no one can hear you scream. */
+#$i_stdlib I_STDLIB
+#ifdef I_STDLIB
+#include <stdlib.h>
+#endif
+#define FILE_ptr(fp) $stdio_ptr
+#define FILE_cnt(fp) $stdio_cnt
+#include <sys/types.h>
+int main() {
+ FILE *fp = fopen("try.c", "r");
+ int c;
+ char *ptr;
+ size_t cnt;
+ if (!fp) {
+ puts("Fail even to read");
+ exit(1);
+ }
+ c = getc(fp); /* Read away the first # */
+ if (c == EOF) {
+ puts("Fail even to read");
+ exit(1);
+ }
+ if (!(
+ 18 <= FILE_cnt(fp) &&
+ strncmp(FILE_ptr(fp), "include <stdio.h>\n", 18) == 0
+ )) {
+ puts("Fail even to read");
+ exit (1);
+ }
+ ptr = (char*) FILE_ptr(fp);
+ cnt = (size_t)FILE_cnt(fp);
+
+ FILE_ptr(fp) += 42;
+
+ if ((char*)FILE_ptr(fp) != (ptr + 42)) {
+ printf("Fail ptr check %p != %p", FILE_ptr(fp), (ptr + 42));
+ exit (1);
+ }
+ if (FILE_cnt(fp) <= 20) {
+ printf ("Fail (<20 chars to test)");
+ exit (1);
+ }
+ if (strncmp(FILE_ptr(fp), "Eat dust sed :-) */\n", 20) != 0) {
+ puts("Fail compare");
+ exit (1);
+ }
+ if (cnt == FILE_cnt(fp)) {
+ puts("Pass_unchanged");
+ exit (0);
+ }
+ if (FILE_cnt(fp) == (cnt - 42)) {
+ puts("Pass_changed");
+ exit (0);
+ }
+ printf("Fail count was %d now %d\n", cnt, FILE_cnt(fp));
+ return 1;
+