<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 3.2//EN">
<html> <head>
<title>Netpbm subroutine library: pm_tmpfile() function</title>
<meta name="manual_section" content="3">
</head>
<body>
<h1>pm_tmpfile()</h1>
Updated: 22 July 2004
<br>
<h2>NAME</h2>
pm_tmpfile() - create a temporary unnamed file
<h2>SYNOPSIS</h2>
<pre>
#include <netpbm/pm.h>
FILE *
pm_tmpfile(void);
</pre>
<h2>EXAMPLE</h2>
<p>This simple example creates a temporary file, writes "hello
world" to it, then reads back and prints those contents.
<pre>
#include <netpbm/pm.h>
FILE * myfileP;
myfile = pm_tmpfile();
fprintf(myfile, "hello world\n");
fseek(myfileP, 0, SEEK_SET);
fread(buffer, sizeof(buffer), 1, myfileP);
fprintf(STDOUT, "temp file contains '%s'\n", buffer);
fclose(myfileP);
</pre>
<h2>DESCRIPTION</H2>
<p>This library function is part of <a href="index.html">Netpbm</a>.
<p><b>pm_tmpfile()</b> creates and opens an unnamed temporary file.
It is basically the same thing as the standard C library
<b>tmpfile()</b> function, except that it uses the <b>TMPFILE</B>
environment variable to decide where to create the temporary file.
If <b>TMPFILE</b> is not set or is set to something unusable (e.g.
too long), <b>pm_tmpfile()</b> falls back to the value of the
standard C library symbol <b>P_tmpdir</b>, just like <b>tmpfile()</b>.
<p>Unlike <b>tmpfile()</b>, <b>pm_tmpfile()</b> never returns NULL.
If it fails, it issues a message to Standard Error and aborts the
program, like most libnetpbm routines do.
<p>If you need to refer to the temporary file by name, use
<b>pm_make_tmpfile()</b> instead.
<h2>HISTORY</h2>
<p><b>pm_tmpfile()</b> was introduced in Netpbm 10.20 (January 2004).
</body>
</html>