8.26

learn

• origin shell code in pic 8-23, pic 8-24, pic 8-25
• how to use waitpid in pic 8-18
• how to wait child process in pic 8-42

and write a job management module

compose them and the little shell is born.

add bg fg jobs command to origin shell program

!INCLUDE "./code/shell/shell.c"

job management module. signal handlers are the key part

!INCLUDE "./code/shell/job.c"

test it

(cd chapter8/code/shell; make && ./shell)

ps: ./loop is a dead loop program, ./sleep sleeps 5 secs and exit.