int cmd_bg(tok_t arg[]){
long pid = 0;
process *p;
if(arg[0]){
pid = strtol(arg[0], NULL, 10);
for(p = first_process; p ; p = p->next){
if(p->pid == pid){
put_process_in_background(p,1);
return 0;
}
}
return -1;
}
else{
for(p = first_process; p->next; p = p->next){
}
p = p->prev;
if(p != first_process){
put_process_in_background(p,1);
return 0;
}
else{
return -1;
}
}
}
/* 06/22/2015 added thinkhy
* Mark a stopped process as being running again.
*/
void continue_process(pid_t pid, int foreground) {
process *p;
for(p = first_process; p&&p->pid != pid; p = p->next);
if(p == NULL) return;
mark_process_as_running(p);
if (foreground)
put_process_in_foreground(p, 1);
else
put_process_in_background(p, 1);
}
int manage_process(tok_t arg[], bool foreground) {
process *p;
pid_t pid = 0;
if (arg[0]) pid = (pid_t)atoi(arg[0]);
p = find_process(pid);
if (!p) {
printf("No such process: ");
if (pid == 0) printf("most recently launched.\n");
else printf("%d.\n", pid);
} else {
p->stopped = false;
if (foreground) {
p->background = false;
put_process_in_foreground(p, true);
} else {
p->background = true;
put_process_in_background(p, true);
}
}
return 1;
}
void run_program(tok_t *t, char *s) {
// execute another program specified in command
process* proc;
if ((proc = create_process(s)) != NULL) {
add_process(proc);
pid_t pid = fork();
// both parent and child should set put the child into its own process group
if (pid == 0) {
proc->pid = getpid();
launch_process(proc);
} else {
proc->pid = pid;
if (shell_is_interactive) {
setpgid(proc->pid, proc->pid);
}
if (proc->background) {
put_process_in_background(proc, false);
} else {
put_process_in_foreground(proc, false);
}
}
}
}
