$ make
$ ./a.out
Added func overkill, pinfo and kjob
main.c :main file
def.c: func defintions and general funcs.
ls.c: func def for ls implementation of ls.
proc.c :fun def for pinfo and background check.
1.gen_prompt() prints the prompt
2.builtin func in main.c
3.4.ls in ls.c using stat structure
5.pinfo using /proc/pid/stat{,m}
6.bg check using waitpid check
7.history is saved to .hist file
8.Redirection in redir.c
9.Piping in pipe.c
10.jobs,kjob,fg,bg,setenv,unsetenv,quit,overkill,ctrz,ctrlc are in their specific files