1 /* Derived from the test case in
2    https://sourceware.org/bugzilla/show_bug.cgi?id=1078.  */
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <unistd.h>
6 
7 #define OUT_SIZE 10000
8 
9 
10 static int fd;
11 
12 static void prepare (void);
13 #define PREPARE(argc, argv) prepare ()
14 
15 static int do_test (void);
16 #define TEST_FUNCTION do_test ()
17 
18 #include "../test-skeleton.c"
19 
20 
21 static void
prepare(void)22 prepare (void)
23 {
24   fd = create_temp_file ("tst-fwrite.", NULL);
25   if (fd == -1)
26     {
27       puts ("cannot create temporary file");
28       exit (1);
29     }
30 }
31 
32 
33 static int
do_test(void)34 do_test (void)
35 {
36   FILE* f = fdopen (fd, "w+");
37   if (f == NULL) {
38     puts ("cannot create stream");
39     return 1;
40   }
41   puts ("Opened temp file");
42 
43   if (fwrite ("a", 1, 1, f) != 1)
44     {
45       puts ("1st fwrite failed");
46       return 1;
47     }
48   puts ("Wrote a byte");
49   fflush (f);
50 
51   char buffer[10000];
52   size_t i = fread (buffer, 1, sizeof (buffer), f);
53   printf ("Read %zu bytes\n", i);
54 
55   for (i = 0; i < OUT_SIZE; i++)
56     {
57       if (fwrite ("n", 1, 1, f) != 1)
58 	{
59 	  printf ("fwrite in loop round %zu failed\n", i);
60 	  return 1;
61 	}
62 
63       if ((i + 1) % 1000 == 0)
64 	printf ("wrote %zu bytes ...\n", i + 1);
65     }
66 
67   printf ("Wrote %i bytes [done]\n", OUT_SIZE);
68 
69   return 0;
70 }
71