changeset 101:ce1d385f4f89

* Use kill(pid, 0) instead of /proc or sysctl blather for looking up pids
* Add OpenProcess call for Win32

--- a/base/System.cpp	Fri May 05 11:35:47 2006 +0000
+++ b/base/System.cpp	Fri May 05 12:34:51 2006 +0000
@@ -15,17 +15,8 @@
 
 #include "System.h"
 
-#ifdef __APPLE__
-#include <sys/types.h>
-#include <sys/sysctl.h>
-#else
 #ifndef _WIN32
-#include <unistd.h>
-#include <cstdio>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <errno.h>
-#endif
+#include <signal.h>
 #endif
 
 #include <iostream>
@@ -53,66 +44,24 @@
 ProcessStatus
 GetProcessStatus(int pid)
 {
-#ifdef __APPLE__
-
-    // See
-    // http://tuvix.apple.com/documentation/Darwin/Reference/ManPages/man3/sysctl.3.html
-    // http://developer.apple.com/qa/qa2001/qa1123.html
-
-    int name[] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, 0, 0 };
-    name[3] = pid;
-
-    int err;
-    size_t length = 0;
-
-    if (sysctl(name, 4, 0, &length, 0, 0)) {
-        perror("GetProcessStatus: sysctl failed");
+#ifdef _WIN32
+    DWORD handle = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE, pid);
+    if (!handle) {
+        return ProcessNotRunning;
+    } else {
+        CloseHandle(handle);
+        return ProcessRunning;
+    }
+#else
+    if (kill(getpid(), 0) == 0) {
+        if (kill(pid, 0) == 0) {
+            return ProcessRunning;
+        } else {
+            return ProcessNotRunning;
+        }
+    } else {
         return UnknownProcessStatus;
     }
-
-    if (length > 0) return ProcessRunning;
-    else return ProcessNotRunning;
-
-#elsif _WIN32
-
-    return UnknownProcessStatus;
-
-#else
-
-    char filename[50];
-    struct stat statbuf;
-
-    // Looking up the pid in /proc is worth a try on any POSIX system,
-    // I guess -- it'll always compile and it won't return false
-    // negatives if we do this first check:
-
-    sprintf(filename, "/proc/%d", (int)getpid());
-
-    int err = stat(filename, &statbuf);
-
-    if (err || !S_ISDIR(statbuf.st_mode)) {
-        // If we can't even use it to tell whether we're running or
-        // not, then clearly /proc is no use on this system.
-        return UnknownProcessStatus;
-    }
-
-    sprintf(filename, "/proc/%d", (int)pid);
-
-    err = stat(filename, &statbuf);
-
-    if (!err) {
-        if (S_ISDIR(statbuf.st_mode)) {
-            return ProcessRunning;
-        } else {
-            return UnknownProcessStatus;
-        }
-    } else if (errno == ENOENT) {
-        return ProcessNotRunning;
-    } else {
-        perror("stat failed");
-        return UnknownProcessStatus;
-    }
-
 #endif
 }