On win32, there is currently no way to get the equivalent function of

the "ps" argument list on Unix - meaning that there is no way to
identify for example the stats processors or the bgwriter.

This patch adds this functionality, in a bit of a crufty way. It creates
a kernel Event object with the name of what would be in the title. This
can be viewed using for example Process Explorer.

It's been very handy for me during both debugging and using. I haven't
figured a better way, but perhaps someone has one that's less crufty? If
not, here is at least a working patch :-)

Magnus Hagander

Author: bmomjian

src/backend/utils/misc/ps_status.c

@@ -5,7 +5,7 @@
  * to contain some useful information. Mechanism differs wildly across
  * platforms.
  *
- * $PostgreSQL: pgsql/src/backend/utils/misc/ps_status.c,v 1.21 2004/08/29 05:06:51 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/misc/ps_status.c,v 1.22 2004/12/02 22:28:22 momjian Exp $
  *
  * Copyright (c) 2000-2004, PostgreSQL Global Development Group
  * various details abducted from various places
@@ -65,6 +65,8 @@ extern char **environ;
 #define PS_USE_CHANGE_ARGV
 #elif defined(__linux__) || defined(_AIX) || defined(__sgi) || (defined(sun) && !defined(BSD)) || defined(ultrix) || defined(__ksr__) || defined(__osf__) || defined(__QNX__) || defined(__svr4__) || defined(__svr5__) || defined(__darwin__)
 #define PS_USE_CLOBBER_ARGV
+#elif defined (WIN32)
+#define PS_USE_WIN32
 #else
 #define PS_USE_NONE
 #endif
@@ -95,6 +97,28 @@ static size_t ps_buffer_fixed_size;		/* size of the constant prefix */
 static int	save_argc;
 static char **save_argv;
 
+#ifdef WIN32
+	/*
+	 * Win32 does not support showing any changed arguments. To make it
+	 * at all possible to track which backend is doing what, we create
+	 * a named object that can be viewed with for example Process Explorer
+	 */
+static HANDLE ident_handle = INVALID_HANDLE_VALUE;
+static void pgwin32_update_ident(char *ident)
+{
+	char name[PS_BUFFER_SIZE+32];
+
+	if (ident_handle != INVALID_HANDLE_VALUE)
+		CloseHandle(ident_handle);
+
+	sprintf(name,"pgident: %s",ident);
+
+	ident_handle = CreateEvent(NULL,
+							   TRUE,
+							   FALSE,
+							   name);
+}
+#endif
 
 /*
  * Call this early in startup to save the original argc/argv values.
@@ -267,6 +291,11 @@ init_ps_display(const char *username, const char *dbname,
 #endif
 
 	ps_buffer_fixed_size = strlen(ps_buffer);
+
+#ifdef WIN32
+	pgwin32_update_ident(ps_buffer);
+#endif
+
 #endif   /* not PS_USE_NONE */
 }
 
@@ -327,6 +356,11 @@ set_ps_display(const char *activity)
 		MemSet(ps_buffer + buflen, PS_PADDING, ps_buffer_size - buflen);
 	}
 #endif   /* PS_USE_CLOBBER_ARGV */
+
+#ifdef WIN32
+	pgwin32_update_ident(ps_buffer);
+#endif
+
 #endif   /* not PS_USE_NONE */
 }