6.8 tmpfile64—create a large temporary file

Synopsis

#include <stdio.h>
FILE *tmpfile64(void);

FILE *_tmpfile64_r(void *reent);

Description
Create a large 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 file may be larger than 2GB.

The alternate function _tmpfile64_r is a reentrant version. The argument reent is a pointer to a reentrancy structure.

Both tmpfile64 and _tmpfile64_r are only defined if __LARGE64_FILES is defined.


Returns
tmpfile64 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.


Portability
tmpfile64 is a glibc extension.

Supporting OS subroutines required: close, fstat, getpid, isatty, lseek64, open64, read, sbrk, write.

tmpfile64 also requires the global pointer environ.