NAME

       mktemp - make a unique temporary filename

SYNOPSIS

       #include <stdlib.h>

       char *mktemp(char *template);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       mktemp():
           Since glibc 2.12:
               (_XOPEN_SOURCE >= 500) && ! (_POSIX_C_SOURCE >= 200112L)
                   || /* Glibc since 2.19: */ _DEFAULT_SOURCE
                   || /* Glibc <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE
           Before glibc 2.12:
               _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500

DESCRIPTION

       Never use this function; see BUGS.

       The  mktemp()  function  generates a unique temporary filename from template.  The last six characters of
       template must be XXXXXX and these are replaced with a string that makes the filename  unique.   Since  it
       will be modified, template must not be a string constant, but should be declared as a character array.

RETURN VALUE

       The  mktemp()  function  always  returns  template.   If a unique name was created, the last six bytes of
       template will have been modified in such a way that the resulting name is unique (i.e.,  does  not  exist
       already)  If  a  unique  name could not be created, template is made an empty string, and errno is set to
       indicate the error.

ERRORS

       EINVAL The last six characters of template were not XXXXXX.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌──────────┬───────────────┬─────────┐
       │Interface │ Attribute     │ Value   │
       ├──────────┼───────────────┼─────────┤
       │mktemp()  │ Thread safety │ MT-Safe │
       └──────────┴───────────────┴─────────┘

CONFORMING TO

       4.3BSD, POSIX.1-2001.  POSIX.1-2008 removes the specification of mktemp().

BUGS

       Never use mktemp().  Some implementations follow 4.3BSD and replace XXXXXX by the current process ID  and
       a single letter, so that at most 26 different names can be returned.  Since on the one hand the names are
       easy to guess, and on the other hand there is a race between testing whether the name exists and  opening
       the file, every use of mktemp() is a security risk.  The race is avoided by mkstemp(3) and mkdtemp(3).

SEE ALSO

       mktemp(1), mkdtemp(3), mkstemp(3), tempnam(3), tmpfile(3), tmpnam(3)

COLOPHON

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