1 files changed, 51 insertions, 0 deletions
diff --git a/user/idle.c b/user/idle.c
new file mode 100644
index 0000000..dbce885
--- /dev/null
+++ b/user/idle.c
@@ -0,0 +1,51 @@
+#include <common.h>
+
+/**
+** Idle process:  write, getpid, gettime, exit
+**
+** Reports itself, then loops forever delaying and printing a character.
+** MUST NOT SLEEP, as it must always be available in the ready queue 
+** when there is no other process to dispatch.
+**
+** Invoked as:	idle
+*/
+
+USERMAIN( main ) {
+	// this is the character we will repeatedly print
+	char ch = '.';
+
+	// ignore the command-line arguments
+	(void) argc;
+	(void) argv;
+
+	// get some current information
+	uint_t pid = getpid();
+	uint32_t now = gettime();
+	enum priority_e prio = getprio();
+
+	char buf[128];
+	sprint( buf, "Idle [%d], started @ %u\n", pid, prio, now );
+	cwrites( buf );
+	
+	// report our presence on the console
+	cwrites( "Idle started\n" );
+
+	write( CHAN_SIO, &ch, 1 );
+
+	// idle() should never block - it must always be available
+	// for dispatching when we need to pick a new current process
+
+	for(;;) {
+		DELAY(LONG);
+		write( CHAN_SIO, &ch, 1 );
+	}
+
+	// we should never reach this point!
+	now = gettime();
+	sprint( buf, "Idle [%d] EXITING @ %u!?!?!\n", pid, now );
+	cwrites( buf );
+
+	exit( 1 );
+
+	return( 42 );
+}