umask(S)                       6 January 1993                       umask(S)


 Name

    umask - set and get file creation mask

 Syntax


    cc  . . .  -lc


    #include <sys/types.h>
    #include <sys/stat.h>

    mode_t umask (cmask)
    mode_t cmask;


 Description

    The umask routine sets the process's file mode creation mask to the argu-
    ment cmask and returns the previous value of the mask.  Only the file
    permission mode bits of cmask (see stat.h) and of the process's file mode
    creation mask are used.

    The process's file mode creation mask is used by creat(S), open(S),
    mkdir(S), and mkfifo(S) to turn off permission bits in each routine's
    specified mode argument.  Bit positions that are set in cmask are cleared
    in the mode of the created file.

 Return value

    The previous value of the file mode creation mask is returned.  No errors
    are defined for the umask routine.

 See also

    creat(S), mkdir(C), mknod(S), open(S)

 Standards conformance

    umask conforms with:
    AT&T SVID Issue 2;
    X/Open Portability Guide, Issue 3, 1989;
    IEEE POSIX Std 1003.1-1990 System Application Program Interface (API) [C
    Language] (ISO/IEC 9945-1);
    and NIST FIPS 151-1.