|
PROLOG | NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | EXAMPLES | APPLICATION USAGE | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
TMPFILE(3P) POSIX Programmer's Manual TMPFILE(3P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
tmpfile — create a temporary file
#include <stdio.h>
FILE *tmpfile(void);
The functionality described on this reference page is aligned with
the ISO C standard. Any conflict between the requirements described
here and the ISO C standard is unintentional. This volume of
POSIX.1‐2008 defers to the ISO C standard.
The tmpfile() function shall create a temporary file and open a
corresponding stream. The file shall be automatically deleted when
all references to the file are closed. The file is opened as in
fopen() for update (w+), except that implementations may restrict the
permissions, either by clearing the file mode bits or setting them to
the value S_IRUSR | S_IWUSR.
In some implementations, a permanent file may be left behind if the
process calling tmpfile() is killed while it is processing a call to
tmpfile().
An error message may be written to standard error if the stream
cannot be opened.
Upon successful completion, tmpfile() shall return a pointer to the
stream of the file that is created. Otherwise, it shall return a
null pointer and set errno to indicate the error.
The tmpfile() function shall fail if:
EINTR A signal was caught during tmpfile().
EMFILE All file descriptors available to the process are currently
open.
EMFILE {STREAM_MAX} streams are currently open in the calling
process.
ENFILE The maximum allowable number of files is currently open in the
system.
ENOSPC The directory or file system which would contain the new file
cannot be expanded.
EOVERFLOW
The file is a regular file and the size of the file cannot be
represented correctly in an object of type off_t.
The tmpfile() function may fail if:
EMFILE {FOPEN_MAX} streams are currently open in the calling process.
ENOMEM Insufficient storage space is available.
The following sections are informative.
Creating a Temporary File
The following example creates a temporary file for update, and
returns a pointer to a stream for the created file in the fp
variable.
#include <stdio.h>
...
FILE *fp;
fp = tmpfile ();
It should be possible to open at least {TMP_MAX} temporary files
during the lifetime of the program (this limit may be shared with
tmpnam()) and there should be no limit on the number simultaneously
open other than this limit and any limit on the number of open file
descriptors or streams ({OPEN_MAX}, {FOPEN_MAX}, {STREAM_MAX}).
None.
None.
Section 2.5, Standard I/O Streams, fopen(3p), mkdtemp(3p),
tmpnam(3p), unlink(3p)
The Base Definitions volume of POSIX.1‐2008, stdio.h(0p)
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 TMPFILE(3P)
Pages that refer to this page: stdio.h(0p), exit(3p), mkdtemp(3p), stdin(3p), tempnam(3p), tmpnam(3p)