newlib-cygwin/newlib/libc/stdio64/tmpfile64.c

94 lines
2.0 KiB
C

/*
FUNCTION
<<tmpfile64>>---create a large temporary file
INDEX
tmpfile64
INDEX
_tmpfile64_r
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>>.
*/
#include <stdio.h>
#include <reent.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/stat.h>
#ifndef O_BINARY
# define O_BINARY 0
#endif
#ifdef __LARGE64_FILES
FILE *
_tmpfile64_r (struct _reent *ptr)
{
FILE *fp;
int e;
char *f;
char buf[L_tmpnam];
int fd;
do
{
if ((f = _tmpnam_r (ptr, buf)) == NULL)
return NULL;
fd = _open64_r (ptr, f, O_RDWR | O_CREAT | O_EXCL | O_BINARY,
S_IRUSR | S_IWUSR);
}
while (fd < 0 && _REENT_ERRNO(ptr) == EEXIST);
if (fd < 0)
return NULL;
fp = _fdopen64_r (ptr, fd, "wb+");
e = _REENT_ERRNO(ptr);
if (!fp)
_close_r (ptr, fd);
(void) _remove_r (ptr, f);
_REENT_ERRNO(ptr) = e;
return fp;
}
#ifndef _REENT_ONLY
FILE *
tmpfile64 (void)
{
return _tmpfile64_r (_REENT);
}
#endif
#endif /* __LARGE64_FILES */