tempnam(3) [php man page]

TEMPNAM(3)								 1								TEMPNAM(3)

tempnam - Create file with unique file name

SYNOPSIS

       string tempnam (string  $dir, string  $prefix)

DESCRIPTION

	Creates  a file with a unique filename, with access permission set to 0600, in the specified directory. If the directory does not exist or
       is not writable, tempnam(3) may generate a file in the system's temporary directory, and return the full path to that file,  including  its
       name.

PARAMETERS

	      o $dir
		- The directory where the temporary filename will be created.

	      o $prefix
		- The prefix of the generated temporary filename.

	      Note

		      Windows uses only the first three characters of prefix.

RETURN VALUES

	Returns the new temporary filename (with path), or FALSE on failure.

CHANGELOG

       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 4.0.3	|						    |
       |	|						    |
       |	|  This  function's  behavior changed in 4.0.3. The |
       |	| temporary file is also created to  avoid  a  race |
       |	| condition  where  the  file  might  appear in the |
       |	| filesystem between the time the string was gener- |
       |	| ated	and before the script gets around to creat- |
       |	| ing the file. Note, that you need to	remove	the |
       |	| file	in case you need it no more, it is not done |
       |	| automatically.				    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES

       Example #1

	      tempnam(3) example

	      <?php
	      $tmpfname = tempnam("/tmp", "FOO");

	      $handle = fopen($tmpfname, "w");
	      fwrite($handle, "writing to tempfile");
	      fclose($handle);

	      // do here something

	      unlink($tmpfname);
	      ?>

NOTES

       Note

	       If PHP cannot create a file in the specified $dir parameter, it falls back on the system default. On NTFS this also happens if  the
	      specified $dir contains more than 65534 files.

SEE ALSO

       tmpfile(3), sys_get_temp_dir(3), unlink(3).

PHP Documentation Group 														TEMPNAM(3)

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

NAME

       tempnam - create a name for a temporary file

SYNOPSIS

       #include <stdio.h>

       char *tempnam(const char *dir, const char *pfx);

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

       tempnam(): _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

       The tempnam() function returns a pointer to a string that is a valid filename, and such that a file with this name did not exist when temp-
       nam() checked.  The filename suffix of the pathname generated will start with pfx in case pfx is a non-NULL string of at most  five  bytes.
       The directory prefix part of the pathname generated is required to be "appropriate" (often that at least implies writable).

       Attempts to find an appropriate directory go through the following steps:

       a) In case the environment variable TMPDIR exists and contains the name of an appropriate directory, that is used.

       b) Otherwise, if the dir argument is non-NULL and appropriate, it is used.

       c) Otherwise, P_tmpdir (as defined in <stdio.h>) is used when appropriate.

       d) Finally an implementation-defined directory may be used.

       The string returned by tempnam() is allocated using malloc(3) and hence should be freed by free(3).

RETURN VALUE

       The tempnam() function returns a pointer to a unique temporary filename, or NULL if a unique name cannot be generated.

ERRORS

       ENOMEM Allocation of storage failed.

CONFORMING TO

       SVr4, 4.3BSD, POSIX.1-2001.  POSIX.1-2008 marks tempnam() as obsolete.

NOTES

       Although  tempnam() generates names that are difficult to guess, it is nevertheless possible that between the time that tempnam() returns a
       pathname, and the time that the program opens it, another program might create that pathname using open(2), or  create  it  as  a  symbolic
       link.  This can lead to security holes.	To avoid such possibilities, use the open(2) O_EXCL flag to open the pathname.	Or better yet, use
       mkstemp(3) or tmpfile(3).

       SUSv2 does not mention the use of TMPDIR; glibc will use it only when the program is not set-user-ID.  On SVr4, the directory used under d)
       is /tmp (and this is what glibc does).

       Because it dynamically allocates memory used to return the pathname, tempnam() is reentrant, and thus thread safe, unlike tmpnam(3).

       The  tempnam()  function  generates a different string each time it is called, up to TMP_MAX (defined in <stdio.h>) times.  If it is called
       more than TMP_MAX times, the behavior is implementation defined.

       tempnam() uses at most the first five bytes from pfx.

       The glibc implementation of tempnam() will fail with the error EEXIST upon failure to find a unique name.

BUGS

       The precise meaning of "appropriate" is undefined; it is unspecified how accessibility of a directory is determined.

       Never use this function.  Use mkstemp(3) or tmpfile(3) instead.

SEE ALSO

       mkstemp(3), mktemp(3), tmpfile(3), tmpnam(3)

COLOPHON

       This page is part of release 3.27 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/.

								    2008-08-06								TEMPNAM(3)