Defined EOF as -1 in stdio.h.

Implemented the sprintf() library function in lib/stdio.c which uses the
vsprintf() function.

Implemented a very primative controlling TTY for each process. This is
achieved by a switch in the sys_puts system call which uses the 'ctty'
element of the process' task structure to determine an appropriate I/O
channel. A negative ctty value doesn't equate to any I/O channel
effectively disabling the process' output.

Added the sys_ctty system call which allows a process to set it's own
ctty value.

Removed the sys_rsputs system call. Output to serial is now performed by
the process first setting it's ctty value to 1, then invoking sys_puts.

1 files changed, 8 insertions, 3 deletions

diff --git a/usrbin/main.c b/usrbin/main.c
index 8c8d2dc..68f1a5c 100644
--- a/usrbin/main.c
+++ b/usrbin/main.c
@@ -9,6 +9,8 @@ void sighandler(int sig) {
 }
 
 void pid1(void) {
+  printf("We did it ma!\n");
+
   signal(SIGALRM, &sighandler);
   alarm(2);
   pause();
@@ -22,6 +24,8 @@ void pid1(void) {
 void pid2(void) {
   int x = 0;
 
+  printf("We did it ma!\n");
+
   while(1) {
     sleep(1);
     printf("0x%04x:0x%08x: 0x%08x, 0x%08x\n", getpid(), (uint32_t) getpdir(), time(), x++);
@@ -29,9 +33,10 @@ void pid2(void) {
 }
 
 void main(void) {
-  printf("We did it ma!\n");
-
-  if(getpid() == 1)
+  if(getpid() == 1) {
+    ctty(1);
     pid1();
+  }
+
   pid2();
 }