Previously this file would fail to compile with the following error:
$ gcc manual/examples/db.c
db.c: In function ‘main’:
db.c:37:7: error: implicit declaration of function ‘printf’ [-Wimplicit-function-declaration]
37 | printf ("Couldn't find out about user %d.\n", (int) me);
| ^~~~~~
db.c:23:1: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
22 | #include <stdlib.h>
+++ |+#include <stdio.h>
23 |
db.c:37:7: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
37 | printf ("Couldn't find out about user %d.\n", (int) me);
| ^~~~~~
db.c:37:7: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
db.c:42:3: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
42 | printf ("I am %s.\n", my_passwd->pw_gecos);
| ^~~~~~
db.c:42:3: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
+#include <stdio.h>
int
main (void)