


Fcntl(3p)        Perl Programmers Reference Guide       Fcntl(3p)


NAME
       Fcntl - load the C Fcntl.h defines

SYNOPSIS
           use Fcntl;
           use Fcntl qw(:DEFAULT :flock);

DESCRIPTION
       This module is just a translation of the C fcntl.h file.
       Unlike the old mechanism of requiring a translated
       fcntl.ph file, this uses the h2xs program (see the Perl
       source distribution) and your native C compiler.  This
       means that it has a far more likely chance of getting the
       numbers right.

NOTE
       Only "#define" symbols get translated; you must still
       correctly pack up your own arguments to pass as args for
       locking functions, etc.

EXPORTED SYMBOLS
       By default your system's F_* and O_* constants (eg,
       F_DUPFD and O_CREAT) and the FD_CLOEXEC constant are
       exported into your namespace.

       You can request that the flock() constants (LOCK_SH,
       LOCK_EX, LOCK_NB and LOCK_UN) be provided by using the tag
       ":flock".  See Exporter.

       You can request that the old constants (FAPPEND, FASYNC,
       FCREAT, FDEFER, FEXCL, FNDELAY, FNONBLOCK, FSYNC, FTRUNC)
       be provided for compatibility reasons by using the tag
       ":Fcompat".  For new applications the newer versions of
       these constants are suggested (O_APPEND, O_ASYNC, O_CREAT,
       O_DEFER, O_EXCL, O_NDELAY, O_NONBLOCK, O_SYNC, O_TRUNC).

       For ease of use also the SEEK_* constants (for seek() and
       sysseek(), e.g. SEEK_END) and the S_I* constants (for
       chmod() and stat()) are available for import.  They can be
       imported either separately or using the tags ":seek" and
       ":mode".

       Please refer to your native fcntl(2), open(2), fseek(3),
       lseek(2) (equal to Perl's seek() and sysseek(),
       respectively), and chmod(2) documentation to see what
       constants are implemented in your system.

       See perlopentut to learn about the uses of the O_*
       constants with sysopen().

       See "seek" in perlfunc and "sysseek" in perlfunc about the
       SEEK_* constants.

       See "stat" in perlfunc about the S_I* constants.



perl v5.10.1                2008-09-29                          1


