Previously this file would fail to compile with the following error:
$ gcc manual/examples/mbstouwcs.c
manual/examples/mbstouwcs.c: In function ‘mbstouwcs’:
manual/examples/mbstouwcs.c:34:11: error: ‘errno’ undeclared (first use in this function)
34 | errno = EILSEQ;
| ^~~~~
manual/examples/mbstouwcs.c:5:1: note: ‘errno’ is defined in header ‘<errno.h>’; this is probably fixable by adding ‘#include <errno.h>’
4 | #include <wchar.h>
+++ |+#include <errno.h>
5 |
manual/examples/mbstouwcs.c:34:11: note: each undeclared identifier is reported only once for each function it appears in
34 | errno = EILSEQ;
| ^~~~~
manual/examples/mbstouwcs.c:34:19: error: ‘EILSEQ’ undeclared (first use in this function)
34 | errno = EILSEQ;
| ^~~~~~
manual/examples/mbstouwcs.c:47:20: error: implicit declaration of function ‘towupper’ [-Wimplicit-function-declaration]
47 | *wcp++ = towupper (wc);
| ^~~~~~~~
manual/examples/mbstouwcs.c:5:1: note: include ‘<wctype.h>’ or provide a declaration of ‘towupper’
4 | #include <wchar.h>
+++ |+#include <wctype.h>
5 |
manual/examples/mbstouwcs.c:47:20: warning: incompatible implicit declaration of built-in function ‘towupper’ [-Wbuiltin-declaration-mismatch]
47 | *wcp++ = towupper (wc);
| ^~~~~~~~
manual/examples/mbstouwcs.c:47:20: note: include ‘<wctype.h>’ or provide a declaration of ‘towupper’
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
+#include <errno.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
+#include <wctype.h>
/* Do not include the above headers in the example.
*/