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Hello, tech@ readers.

display.c contains function anykey(). This function useses read(2)
system call to read user input.

Let see how read(2) return value is check for errors:

display.c:
....
size_t len;
....
len = read(STDIN_FILENO, &ch, 1);
if (len == -1 && errno == EINTR)
continue;
....

Pay attention that len is tested against -1. len is declared as size_t.
size_t is unsigned data type. Also from read(2) one can see that read(2)
returns not size_t, but ssize_t (two `s'). ssize_t is signed data type.

(~)[1]% grep __size_t /usr/include/machine/_types.h
typedef unsigned long __size_t;

(~)[2]% grep __ssize_t /usr/include/machine/_types.h
typedef long __ssize_t;

Problem: len is declared as unsigned, but is tested against -1. This is
incorrect.

Following diff declares len as ssize_t (with two `s'). It also sorts
headers as style(9) says.

Occasionaly i added sever blank lines for clarity.


--- display.c.original Fri Jul 27 12:27:08 2007
+++ display.c Fri Jul 27 13:35:45 2007
@@ -47,22 +47,23 @@

#include <sys/types.h>
#include <sys/sched.h>
+
+#include <ctype.h>
#include <curses.h>
+#include <err.h>
#include <errno.h>
#include <stdio.h>
-#include <ctype.h>
-#include <err.h>
-#include <signal.h>
#include <stdlib.h>
+#include <signal.h>
#include <string.h>
#include <unistd.h>

-#include "screen.h" /* interface to screen package */
-#include "layout.h" /* defines for screen position layout */
+#include "boolean.h"
#include "display.h"
+#include "layout.h" /* defines for screen position layout */
#include "top.h"
-#include "boolean.h"
#include "machine.h" /* we should eliminate this!!! */
+#include "screen.h" /* interface to screen package */
#include "utils.h"

#ifdef DEBUG
@@ -505,7 +506,7 @@
}

void
-u_endscreen(int hi)
+u_endscreen(void)
{
if (smart_terminal) {
clrtobot();
@@ -827,19 +828,22 @@
anykey(void)
{
int ch;
- size_t len;
+ ssize_t len;

standoutp();
addstrp("Hit any key to continue: ");
standendp();
+
if (smart_terminal)
refresh();
else
fflush(stdout);
+
while (1) {
len = read(STDIN_FILENO, &ch, 1);
if (len == -1 && errno == EINTR)
continue;
+
if (len == 0)
exit(1);
break;