# Fcntl - phpMan

## 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.