1#define _XOPEN_SOURCE 500
2#include <stdio.h>
3#include <stdlib.h>
4#include <locale.h>
5#include <wchar.h>
6
7const char write_chars[] = "ABC"; /* Characters on testfile. */
8const wint_t unget_wchar = L'A'; /* Ungotten wide character. */
9
10char *fname;
11
12
13static int do_test (void);
14#define TEST_FUNCTION do_test ()
15
16#include "../test-skeleton.c"
17
18
19static int
20do_test (void)
21{
22 wint_t wc;
23 FILE *fp;
24 int fd;
25
26 fname = (char *) malloc (size: strlen (test_dir) + sizeof "/bug-ungetwc1.XXXXXX");
27 if (fname == NULL)
28 {
29 puts (s: "no memory");
30 return 1;
31 }
32 strcpy (stpcpy (fname, test_dir), "/bug-ungetwc1.XXXXXX");
33 fd = mkstemp (template: fname);
34 if (fd == -1)
35 {
36 printf (format: "cannot open temporary file: %m\n");
37 return 1;
38 }
39 add_temp_file (name: fname);
40
41 setlocale(LC_ALL, "");
42
43 /* Output to the file. */
44 if ((fp = fdopen (fd, "w")) == NULL)
45 {
46 fprintf (stderr, "Cannot make `%s' file\n", fname);
47 exit (EXIT_FAILURE);
48 }
49
50 fprintf (fp, "%s", write_chars);
51 fclose (fp);
52
53 /* Read from the file. */
54 fp = fopen (fname, "r");
55
56 size_t i = 0;
57 while (!feof (stream: fp))
58 {
59 wc = getwc (stream: fp);
60 if (i >= sizeof (write_chars))
61 {
62 printf (format: "Did not get end-of-file when expected.\n");
63 return 1;
64 }
65 else if (wc != (write_chars[i] ? write_chars[i] : WEOF))
66 {
67 printf (format: "Unexpected %lu from getwc.\n", (unsigned long int) wc);
68 return 1;
69 }
70 i++;
71 }
72 printf (format: "\nThe end-of-file indicator is set.\n");
73
74 /* Unget a wide character. */
75 ungetwc (wc: unget_wchar, stream: fp);
76 printf (format: "< `%lc' is ungotten.\n", unget_wchar);
77
78 /* Check the end-of-file indicator. */
79 if (feof (stream: fp))
80 {
81 printf (format: "The end-of-file indicator is still set.\n");
82 return 1;
83 }
84 else
85 printf (format: "The end-of-file flag is cleared.\n");
86
87 fflush (stdout);
88 fclose (fp);
89
90 return 0;
91}
92

source code of glibc/libio/bug-ungetwc1.c