The xv6 pstree project requires to add a new system call get…

The xv6 pstree prоject requires tо аdd а new system cаll getprоcs. In order to add the new system call getprocs, what C code changes need to be made to the following code fragment in xv6 syscall.c? extern int sys_chdir(void);extern int sys_close(void);…extern int sys_wait(void);extern int sys_write(void);extern int sys_uptime(void);static int (*syscalls[])(void) = {[SYS_fork]    sys_fork,[SYS_exit]    sys_exit,…[SYS_mknod]   sys_mknod,[SYS_unlink]  sys_unlink,[SYS_link]    sys_link,[SYS_mkdir]   sys_mkdir,[SYS_close]   sys_clos,};voidsyscall(void){ int num; num = proc->tf->eax; if(num > 0 && num < NELEM(syscalls) && syscalls[num]) {   proc->tf->eax = syscalls[num](); } else {   cprintf("%d %s: unknown sys call %dn",           proc->pid, proc->name, num);   proc->tf->eax = -1; }}