Added process.c to the build, implemented getpid().

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@5377 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kernel/libroot/posix/unistd/Jamfile

@@ -17,6 +17,7 @@ KernelMergeObject posix_unistd.o :
 	<$(SOURCE_GRIST)>mount.c
 	<$(SOURCE_GRIST)>open.c
 	<$(SOURCE_GRIST)>pipe.c
+	<$(SOURCE_GRIST)>process.c
 	<$(SOURCE_GRIST)>read.c
 	<$(SOURCE_GRIST)>sleep.c
 	<$(SOURCE_GRIST)>terminal.c

src/kernel/libroot/posix/unistd/process.c

@@ -10,6 +10,9 @@
 #include <errno.h>
 
 
+extern thread_id __main_thread_id;
+
+
 // ToDo: implement the process ID functions for real!
 
 
@@ -23,7 +26,8 @@ getpgrp(void)
 pid_t 
 getpid(void)
 {
-	return 0;
+	// this one returns the ID of the main thread
+	return __main_thread_id;
 }