{
    "mode": "info",
    "parameter": "fcntl",
    "section": "",
    "url": "https://www.chedong.com/phpMan.php/info/fcntl/json",
    "generated": "2026-08-03T15:01:05Z",
    "synopsis": "use Fcntl;\nuse Fcntl qw(:DEFAULT :flock);",
    "sections": {
        "NAME": {
            "content": "Fcntl - load the C Fcntl.h defines\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "use Fcntl;\nuse Fcntl qw(:DEFAULT :flock);\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "This module is just a translation of the C fcntl.h file.  Unlike the\nold mechanism of requiring a translated fcntl.ph file, this uses the\nh2xs program (see the Perl source distribution) and your native C\ncompiler.  This means that it has a far more likely chance of getting\nthe numbers right.\n",
            "subsections": []
        },
        "NOTE": {
            "content": "Only \"#define\" symbols get translated; you must still correctly pack up\nyour own arguments to pass as args for locking functions, etc.\n",
            "subsections": []
        },
        "EXPORTED SYMBOLS": {
            "content": "By default your system's F* and O* constants (eg, FDUPFD and\nOCREAT) and the FDCLOEXEC constant are exported into your namespace.\n\nYou can request that the flock() constants (LOCKSH, LOCKEX, LOCKNB\nand LOCKUN) be provided by using the tag \":flock\".  See Exporter.\n\nYou can request that the old constants (FAPPEND, FASYNC, FCREAT,\nFDEFER, FEXCL, FNDELAY, FNONBLOCK, FSYNC, FTRUNC) be provided for\ncompatibility reasons by using the tag \":Fcompat\".  For new\napplications the newer versions of these constants are suggested\n(OAPPEND, OASYNC, OCREAT, ODEFER, OEXCL, ONDELAY, ONONBLOCK,\nOSYNC, OTRUNC).\n\nFor ease of use also the SEEK* constants (for seek() and sysseek(),\ne.g. SEEKEND) and the SI* constants (for chmod() and stat()) are\navailable for import.  They can be imported either separately or using\nthe tags \":seek\" and \":mode\".\n\nPlease refer to your native fcntl(2), open(2), fseek(3), lseek(2)\n(equal to Perl's seek() and sysseek(), respectively), and chmod(2)\ndocumentation to see what constants are implemented in your system.\n\nSee perlopentut to learn about the uses of the O* constants with\nsysopen().\n\nSee \"seek\" in perlfunc and \"sysseek\" in perlfunc about the SEEK*\nconstants.\n\nSee \"stat\" in perlfunc about the SI* constants.\n\nperl v5.34.0                      2026-06-23                      Fcntl(3perl)",
            "subsections": []
        }
    },
    "summary": "Fcntl - load the C Fcntl.h defines",
    "flags": [],
    "examples": [],
    "see_also": []
}