ffserver: cast PID to int64_t before printing

Unfortunately, there is no portable format specifier for PID's.
Furthermore, it is not safe to assume pid_t <= 32 bit in size,
see e.g http://unix.derkeiler.com/Mailing-Lists/AIX-L/2010-08/msg00008.html.
Right now, it is ok to assume pid_t <= 32 bit in size, but this may change in the future.
Also, this patch fixes warning due to lack of an appropriate cast from
http://fate.ffmpeg.org/report.cgi?time=20150820233505&slot=x86-opensolaris-gcc4.3.
Note that this method of handling pid_t is in line with what nginx does.

Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

ffserver.c

@@ -1936,7 +1936,7 @@ static void compute_status(HTTPContext *c)
 
         avio_printf(pb, "<h2>Feed %s</h2>", stream->filename);
         if (stream->pid) {
-            avio_printf(pb, "Running as pid %d.\n", stream->pid);
+            avio_printf(pb, "Running as pid %"PRId64".\n", (int64_t) stream->pid);
 
 #if defined(linux)
             {
@@ -1945,8 +1945,8 @@ static void compute_status(HTTPContext *c)
 
                 /* This is somewhat linux specific I guess */
                 snprintf(ps_cmd, sizeof(ps_cmd),
-                         "ps -o \"%%cpu,cputime\" --no-headers %d",
+                         "ps -o \"%%cpu,cputime\" --no-headers %"PRId64"",
-                         stream->pid);
+                         (int64_t) stream->pid);
 
                  pid_stat = popen(ps_cmd, "r");
                  if (pid_stat) {
@@ -3778,8 +3778,8 @@ static void handle_child_exit(int sig)
             uptime = time(0) - feed->pid_start;
             feed->pid = 0;
             fprintf(stderr,
-                    "%s: Pid %d exited with status %d after %d seconds\n",
+                    "%s: Pid %"PRId64" exited with status %d after %d seconds\n",
-                    feed->filename, pid, status, uptime);
+                    feed->filename, (int64_t) pid, status, uptime);
 
             if (uptime < 30)
                 /* Turn off any more restarts */