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Date: Thu, 09 Oct 2008 18:34:00 -0000
Subject: [Bug c/37785]  New: printf + sleep = problems with output buffer
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From: "alexcastan at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
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PLATFORM

PC i386 + GNU/Linux Ubuntu Hardy 8.04 + GCC 4.2.3
Compiling and Linking options: none.

Excuse my poor English. (By the way, what is "Host triplet", "Target triplet",
"Build triplet"?)

BUG:

"printf" really prints at terminal when finds '\n' character. So if I have a
simple "printf" iteration without '\n' like this ...

  int n;
  for (n=10; n>=0; n--) {
    printf("%d ", n);
    sleep(1);
  };

... it doesn't works like expected. It just waits 10 seconds without printing
anything. After that prints whole line.

Another related problem with printf without '\n' and printf buffer using fork,
but I don't know if it is problem with printf or fork:

  int n, pid;
  for (n=10; n>=0; n--) {
    printf("%d ", n);
    sleep(1);
  };
  pid = fork();
  if (pid == -1)
    printf("Error\n");
  else 
    if (pid == 0)
      printf("I'm the child\n");
    else 
      printf("I'm the parent\n");

it prints TWO times   10 9 8 7 6 5 4 3 2 1 0
It is not that executes two times, but if the fork send again the buffer to the
screen.


-- 
           Summary: printf + sleep = problems with output buffer
           Product: gcc
           Version: 4.2.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: alexcastan at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37785