pop_common.c:5:3: warning: incompatible implicit declaration of built-in function ‘exit’
pop_common.c:10:3: warning: incompatible implicit declaration of built-in function ‘exit’
pop_client.c:61:3: warning: incompatible implicit declaration of built-in function ‘exit’
pop_gui_client.c:58:4: warning: incompatible implicit declaration of built-in function ‘memset’
pop_gui_client.c:72:27: warning: incompatible implicit declaration of built-in function ‘strlen’
pop_gui_client.c:128:3: warning: incompatible implicit declaration of built-in function ‘exit’

--- a/pop_client.c
+++ b/pop_client.c
@@ -1,11 +1,11 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <errno.h>
 #include <glib.h>
-#include <stdio.h>
 #include <netdb.h>
 #include "pop_common.h"
 #include "pop_client.h"
--- a/pop_common.c
+++ b/pop_common.c
@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <stdlib.h>
 void errquit(char *message)
 {
   perror(message);
--- a/pop_gui_client.c
+++ b/pop_gui_client.c
@@ -1,3 +1,5 @@
+#include <stdlib.h>
+#include <string.h>
 #include <netdb.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>