toolchain/gcc/newlib/libc/stdio/tmpfile.c

   1 /*
   2 FUNCTION
   3 <<tmpfile>>---create a temporary file
   4
   5 INDEX
   6         tmpfile
   7 INDEX
   8         _tmpfile_r
   9
  10 ANSI_SYNOPSIS
  11         #include <stdio.h>
  12         FILE *tmpfile(void);
  13
  14         FILE *_tmpfile_r(void *<[reent]>);
  15
  16 TRAD_SYNOPSIS
  17         #include <stdio.h>
  18         FILE *tmpfile();
  19
  20         FILE *_tmpfile_r(<[reent]>)
  21         char *<[reent]>;
  22
  23 DESCRIPTION
  24 Create a temporary file (a file which will be deleted automatically),
  25 using a name generated by <<tmpnam>>.  The temporary file is opened with
  26 the mode <<"wb+">>, permitting you to read and write anywhere in it
  27 as a binary file (without any data transformations the host system may
  28 perform for text files).
  29
  30 The alternate function <<_tmpfile_r>> is a reentrant version.  The
  31 argument <[reent]> is a pointer to a reentrancy structure.
  32
  33 RETURNS
  34 <<tmpfile>> normally returns a pointer to the temporary file.  If no
  35 temporary file could be created, the result is NULL, and <<errno>>
  36 records the reason for failure.
  37
  38 PORTABILITY
  39 Both ANSI C and the System V Interface Definition (Issue 2) require
  40 <<tmpfile>>.
  41
  42 Supporting OS subroutines required: <<close>>, <<fstat>>, <<getpid>>,
  43 <<isatty>>, <<lseek>>, <<open>>, <<read>>, <<sbrk>>, <<write>>.
  44
  45 <<tmpfile>> also requires the global pointer <<environ>>.
  46 */
  47
  48 #include <stdio.h>
  49 #include <errno.h>
  50
  51 FILE *
  52 _DEFUN (_tmpfile_r, (ptr),
  53         struct _reent *ptr)
  54 {
  55   FILE *fp;
  56   int e;
  57   char *f;
  58   char buf[L_tmpnam];
  59
  60   if ((f = _tmpnam_r (ptr, buf)) == NULL)
  61     return NULL;
  62   fp = _fopen_r (ptr, f, "wb+");
  63   e = ptr->_errno;
  64   _CAST_VOID _remove_r (ptr, f);
  65   ptr->_errno = e;
  66   return fp;
  67 }
  68
  69 #ifndef _REENT_ONLY
  70
  71 FILE *
  72 _DEFUN_VOID (tmpfile)
  73 {
  74   return _tmpfile_r (_REENT);
  75 }
  76
  77 #endif