X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=pod%2Fperlfunc.pod;h=67c305ca6bc727253bc0356ea0caa9f30e1e8194;hb=03d70c897754d6af90de9d0ffe2857d000d6f2d7;hp=2fa645d9c29c6550aca7681db9cf61ecb5a4bad4;hpb=c16425f1b01347226d2386c029d71b356d39092d;p=p5sagit%2Fp5-mst-13.2.git diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod index 2fa645d..67c305c 100644 --- a/pod/perlfunc.pod +++ b/pod/perlfunc.pod @@ -2812,19 +2812,25 @@ STDERR: print STDOUT "stdout 2\n"; print STDERR "stderr 2\n"; -If you specify C<< '<&=N' >>, where C is a number, then Perl will do an -equivalent of C's C of that file descriptor; this is more -parsimonious of file descriptors. For example: +If you specify C<< '<&=N' >>, where C is a number, then Perl will +do an equivalent of C's C of that file descriptor; this is +more parsimonious of file descriptors. For example: open(FILEHANDLE, "<&=$fd") + or + open(FILEHANDLE, "<&=", $fd) -Note that if perl is using the standard C libaries fdopen() then on many UNIX systems, -fdopen() is known to fail when file descriptors +Note that if Perl is using the standard C libraries' fdopen() then on +many UNIX systems, fdopen() is known to fail when file descriptors exceed a certain value, typically 255. If you need more file descriptors than that, consider rebuilding Perl to use the C. +You can see whether Perl has been compiled with PerlIO or not by +running C and looking for C line. If C +is C, you have PerlIO, otherwise you don't. + If you open a pipe on the command C<'-'>, i.e., either C<'|-'> or C<'-|'> with 2-arguments (or 1-argument) form of open(), then there is an implicit fork done, and the return value of open is the pid @@ -4291,11 +4297,11 @@ loop control operators described in L or with C. When C is in effect, C sorts LIST according to the current collation locale. See L. -Perl does B guarantee that sort is stable. (In a I sort the -relative order is preserved for elements where the sort comparison used -returns that they are equal.) 5.7 happens to use a mergesort, which is -stable, but 5.6 and earlier used quicksort, which is not. However, do not -assume that future perls will continue to use a stable sort such as mergesort. +Perl does B guarantee that sort is stable. (A I sort +preserves the input order of elements that compare equal.) 5.7 and +5.8 happen to use a stable mergesort, but 5.6 and earlier used quicksort, +which is not stable. Do not assume that future perls will continue to +use a stable sort. Examples: @@ -5510,7 +5516,7 @@ Does the opposite of a C. Or the opposite of a C, depending on how you look at it. Prepends list to the front of the array, and returns the new number of elements in the array. - unshift(ARGV, '-e') unless $ARGV[0] =~ /^-/; + unshift(@ARGV, '-e') unless $ARGV[0] =~ /^-/; Note the LIST is prepended whole, not one element at a time, so the prepended elements stay in the same order. Use C to do the @@ -5622,6 +5628,13 @@ command if the files already exist: $now = time; utime $now, $now, @ARGV; +If the first two elements of the list are C, then the utime(2) +function in the C library will be called with a null second argument. +On most systems, this will set the file's access and modification +times to the current time. (i.e. equivalent to the example above.) + + utime undef, undef, @ARGV; + =item values HASH Returns a list consisting of all the values of the named hash. (In a