mkstemp(3)                                                   mkstemp(3)

  mktemp()

  NAME

    mktemp() - make temporary file name (unique)

  SYNOPSIS

    #include 

    char * mktemp (char *template)
    int mkstemp (char *template)

  DESCRIPTION

    The mktemp(3) function takes the given file name template and overwrites a
    portion of it to create a file name. This file name is unique and suitable
    for use by the application. The template may be any file name with some
    number of X appended to it, for example /tmp/temp.XXXX. The trailing X are
    replaced with the current process number and/or a unique letter
    combination. The number of unique file names mktemp(3) can return depends
    on the number of X provided; six X will result in mktemp(3) testing
    roughly 26**6 combinations.

    The mkstemp(3) function makes the same replacement to the template and
    creates the template file, mode 0600, returning a file descriptor opened
    for reading and writing. This avoids the race between testing for a file's
    existence and opening it for use.

  RETURN VALUES

    The mktemp(3) function returns a pointer to the template on success and
    NULL on failure. The mkstemp(3) function returns -1 if no suitable file
    could be created. If either call fails an error code is placed in the
    global variable errno.

  ERRORS

    The mktemp(3) and mkstemp(3) functions may set errno to one of the
    following values:

    [ENOTDIR]
        The pathname portion of the template is not an existing directory.

    The mktemp(3) and mkstemp(3) functions may also set errno to any value
    specified by the stat(2) function.

    The mkstemp(3) function may also set errno to any value specified by the
    open(2) function.

  SEE ALSO

    chmod(2)

    getpid(2)

    open(2)

    stat(2)

  USAGE NOTES

    All of these functions are thread safe.

    None of these functions are async-signal safe.