compiler/posixc/tmpfile.c

   1 /*
   2     This file has been released into the Public Domain.
   3     $Id$
   4
   5     POSIX.1-2008 function tmpfile().
   6 */
   7
   8 #include <sys/param.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <errno.h>
  12 #include <fcntl.h>
  13 #include <proto/dos.h>
  14 #include <unistd.h>
  15
  16 #define DEBUG 0
  17 #include <aros/debug.h>
  18
  19 /*****************************************************************************
  20
  21     NAME */
  22 #include <stdio.h>
  23
  24         FILE * tmpfile(
  25
  26 /*  SYNOPSIS */
  27         void)
  28
  29 /*  FUNCTION
  30         The tmpfile() function returns a pointer to a stream
  31         associated with a file descriptor returned by the routine
  32         mkstemp(3).  The created file is unlinked before tmpfile()
  33         returns, causing the file to be automatically deleted when the
  34         last reference to it is closed.  The file is opened with the
  35         access value `w+'.  The file is created in the T: directory,
  36         which is the standard AROS temp directory.
  37
  38
  39     INPUTS
  40
  41
  42     RESULT
  43         The tmpfile() function returns a pointer to an open file stream on
  44         success. On error, a NULL pointer is returned and errno is set
  45         appropriately.
  46
  47     ERRORS
  48         The tmpfile() function may fail and set the global variable
  49         errno for any of the errors specified for the library functions
  50         fdopen() or mkstemp().
  51
  52     NOTES
  53
  54     EXAMPLE
  55         #include <errno.h>
  56         #include <stdio.h>
  57         #include <string.h>
  58
  59         main()
  60         {
  61           FILE * fp;
  62
  63           fp = tmpfile();
  64           if ( fp == NULL)
  65           {
  66             perror(strerror(errno));
  67             return;
  68           }
  69
  70           fprintf(fp, "do a bit of writing to the temp file");
  71         }
  72
  73     BUGS
  74         BUG1: The temporary file is neither closed nor deleted. Ideally,
  75         unlink() could be used to mark the temp file for removal (see
  76         BUG1 in the source code) - but I suspect a bug in unlink() itself,
  77         whereby it tries to remove the file straight away, rather than
  78         waiting for all references to it to be closed. The bug is not too
  79         serious, because all temp files are written to the T: directory,
  80         which get zapped when AROS is closed down. However, problems may
  81         exist when you start creating over 26 temp files with the same PID.
  82
  83
  84     SEE ALSO
  85         fopen(), mkstemp()
  86
  87     INTERNALS
  88
  89 ******************************************************************************/
  90 {
  91   #define TEMPLATE "T:temp.XXXXXX"
  92   char * filename;
  93   FILE *fp;
  94
  95   filename = (char *)malloc(MAXPATHLEN);
  96   if (!filename) { puts("FIXME: mktemp() malloc failed"); return NULL;}
  97   strcpy(filename, TEMPLATE);
  98
  99   mktemp(filename);
 100   D(bug("[posixc/tmpfile()] filename: %s\n", filename));
 101   fp = fopen(filename, "w+");
 102   /* unlink(filename); -- see BUG1 in BUGS section */
 103   free(filename);
 104   return fp;
 105
 106 } /* tmpfile() */