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freopen, fclose and stdout

freopen closes stdout, but it seems that fclose doesn't restore it (see sample below).

How can one print to stdout after using freopen?
========= C code : File foo.c : BEGIN =========
#include <stdio.h>
#include <assert.h>

#define FILE_NAME "foobar"

int main ()
FILE* out_fp;
int rc;

remove (FILE_NAME);

printf ( "printf-1\n");

out_fp = freopen (FILE_NAME, "a", stdout);
assert (out_fp);

printf ("printf-2\n");
fprintf (out_fp, "fprintf(out_fp )\n");

rc = fclose (out_fp);
assert (!rc);

printf ("printf-3\n"); // Problematic printf

return 0;
========= C code : File foo.c : END ===========
========= Compilation & Run : BEGIN =========

$ gcc -v
gcc version 3.3.1 (cygming special)

$ gcc -W -Wall foo.c

$ a
// printf-3 missing

$ cat foobar

========= Compilation & Run : END ===========

=============== =============== =======
Alex Vinokur
mailto:al****@c onnect.to
=============== =============== =======

Nov 13 '05 #1
2 12601
Alex Vinokur wrote:
freopen closes stdout, but it seems that fclose doesn't restore it (see sample below).

How can one print to stdout after using freopen?


Nov 13 '05 #2
Alex Vinokur wrote:


freopen closes stdout, but it seems that fclose doesn't restore it (see sample below).

How can one print to stdout after using freopen?

This is Question 12.34 in the comp.lang.c Frequently
Asked Questions (FAQ) list


.... and you're not going to like the answer.

Er*********@sun .com
Nov 13 '05 #3

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