tmpfile(3) Library Functions Manual tmpfile(3)
NAME
tmpfile - create a temporary file
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <stdio.h>
FILE *tmpfile(void);
DESCRIPTION
The tmpfile() function opens a unique temporary file in binary
read/write (w+b) mode. The file will be automatically deleted when it
is closed or the program terminates.
RETURN VALUE
The tmpfile() function returns a stream descriptor, or NULL if a unique
filename cannot be generated or the unique file cannot be opened. In
the latter case, errno is set to indicate the error.
ERRORS
EACCES Search permission denied for directory in file's path prefix.
EEXIST Unable to generate a unique filename.
EINTR The call was interrupted by a signal; see signal(7).
EMFILE The per-process limit on the number of open file descriptors has
been reached.
ENFILE The system-wide limit on the total number of open files has been
reached.
ENOSPC There was no room in the directory to add the new filename.
EROFS Read-only filesystem.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ tmpfile() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
VERSIONS
The standard does not specify the directory that tmpfile() will use.
glibc will try the path prefix P_tmpdir defined in <stdio.h>, and if
that fails, then the directory /tmp.
STANDARDS
C11, POSIX.1-2008.
HISTORY
POSIX.1-2001, C89, SVr4, 4.3BSD, SUSv2.
NOTES
POSIX.1-2001 specifies: an error message may be written to stdout if
the stream cannot be opened.
SEE ALSO
exit(3), mkstemp(3), mktemp(3), tempnam(3), tmpnam(3)
Linux man-pages 6.7 2023-10-31 tmpfile(3)
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