update lab1-8 codes and docs. now version is 0.2

code/lab7/user/forktree.c

@@ -3,7 +3,7 @@
 #include <string.h>
 
 #define DEPTH 4
-#define SLEEP_TIME 400
+
 void forktree(const char *cur);
 
 void
@@ -31,8 +31,6 @@ forktree(const char *cur) {
 
 int
 main(void) {
-    cprintf("forktree process will sleep %d ticks\n",SLEEP_TIME);
-    sleep(SLEEP_TIME);
     forktree("");
     return 0;
 }

code/lab7/user/libs/syscall.c

@@ -70,7 +70,7 @@ sys_pgdir(void) {
     return syscall(SYS_pgdir);
 }
 
-size_t
+int
 sys_gettime(void) {
     return syscall(SYS_gettime);
 }

code/lab7/user/libs/syscall.h

@@ -9,6 +9,7 @@ int sys_kill(int pid);
 int sys_getpid(void);
 int sys_putc(int c);
 int sys_pgdir(void);
+int sys_gettime(void);
 /* FOR LAB6 ONLY */
 void sys_lab6_set_priority(uint32_t priority);
 

code/lab7/user/spin.c

@@ -3,7 +3,7 @@
 
 int
 main(void) {
-    int pid, ret, i ,j;
+    int pid, ret;
     cprintf("I am the parent. Forking the child...\n");
     pid = fork();
     if (pid== 0) {