MKTEMP(3)		   Linux Programmer's Manual		     MKTEMP(3)



NAME
       mktemp - make a unique temporary filename

SYNOPSIS
       #include 

       char *mktemp(char *template);

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

       mktemp(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500

DESCRIPTION
       The  mktemp()  function generates a unique temporary filename from tem-
       plate.  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.

ERRORS
       EINVAL The last six characters of template were not XXXXXX.

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

NOTES
       The prototype is in  for libc4, libc5, glibc1; glibc2 follows
       the Single Unix Specification and has the prototype in .

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	 test-
       ing whether the name exists and opening the file, every use of mktemp()
       is a security risk.  The race is avoided by mkstemp(3).

SEE ALSO
       mkstemp(3), tempnam(3), tmpfile(3), tmpnam(3)

COLOPHON
       This page is part of release 3.22 of the Linux  man-pages  project.   A
       description  of	the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



GNU				  2008-08-06			     MKTEMP(3)