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.