1 files changed, 7 insertions, 12 deletions
diff --git a/kernel/sysproc.c b/kernel/sysproc.c
index 8ca45ba..1de184e 100644
--- a/kernel/sysproc.c
+++ b/kernel/sysproc.c
@@ -10,8 +10,7 @@ uint64
 sys_exit(void)
 {
   int n;
-  if(argint(0, &n) < 0)
-    return -1;
+  argint(0, &n);
   exit(n);
   return 0;  // not reached
 }
@@ -32,19 +31,17 @@ uint64
 sys_wait(void)
 {
   uint64 p;
-  if(argaddr(0, &p) < 0)
-    return -1;
+  argaddr(0, &p);
   return wait(p);
 }
 
 uint64
 sys_sbrk(void)
 {
-  int addr;
+  uint64 addr;
   int n;
 
-  if(argint(0, &n) < 0)
-    return -1;
+  argint(0, &n);
   addr = myproc()->sz;
   if(growproc(n) < 0)
     return -1;
@@ -57,12 +54,11 @@ sys_sleep(void)
   int n;
   uint ticks0;
 
-  if(argint(0, &n) < 0)
-    return -1;
+  argint(0, &n);
   acquire(&tickslock);
   ticks0 = ticks;
   while(ticks - ticks0 < n){
-    if(myproc()->killed){
+    if(killed(myproc())){
       release(&tickslock);
       return -1;
     }
@@ -77,8 +73,7 @@ sys_kill(void)
 {
   int pid;
 
-  if(argint(0, &pid) < 0)
-    return -1;
+  argint(0, &pid);
   return kill(pid);
 }