glibc/libio/bug-mmap-fflush.c

28 lines
544 B
C

/* Test for bug in fflush synchronization behavior. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main (void)
{
FILE *f;
off_t o;
char buffer [1024];
system ("echo 'From foo@bar.com' > test");
f = fopen ("test", "r");
fseek (f, 0, SEEK_END);
o = ftello (f);
fseek (f, 0, SEEK_SET);
fflush (f);
system ("echo 'From bar@baz.edu' >> test");
fseek (f, o, SEEK_SET);
if (fgets (buffer, 1024, f) == NULL)
abort ();
if (strncmp (buffer, "From ", 5) != 0)
abort ();
fclose (f);
exit (0);
}