tmpfile : create a temporary file

Synopsis

#include <stdio.h>
FILE *tmpfile(void);
FILE *_tmpfile_r(void *reent);
```### Description

Create a temporary file (a file which will be deleted automatically), using a name generated by tmpnam. The temporary file is opened with the mode "wb+", permitting you to read and write anywhere in it as a binary file (without any data transformations the host system may perform for text files).

The alternate function _tmpfile_r is a reentrant version. The argument reent is a pointer to a reentrancy structure.### Returns

tmpfile normally returns a pointer to the temporary file. If no temporary file could be created, the result is NULL, and errno records the reason for failure.

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**Authoritative source**: BUSMASTER DITA help source `tmpfile.dita`, compiled into `BUSMASTER.CHM` with the application.