Shell in C

This is a functional shell coded in C language.

Execution

Run the following commands :
make
./shell

Features

• Modular code
• Shell works with the directory from where it was executed as '~'.
• Background and foreground processes supported.
• Shell supports I/O redirection.
• Shell supports piping of commands.
• Shell supports Ctrl+Z to stop a currently running foreground job.
• Shell supports Ctrl+C to terminate a currently running foreground job.
• ';' separated commands supported.
• The commands ls echo pwd pinfo clock remindme cd setenv unsetenv jobs kjob fg bg overkill are in-built in the shell.
• Command jobs lists out all the currently running processes that are recorded by '/proc'.
• Command kjob <jobNumber> <signalNumber> can be used to send a signal to a job.
• Command fg <jobNumber> can be used to bring a job to foreground.
• Command bg <jobNumber> can be used to start a stopped job in the background.
• Command overkill can be used to kill all background jobs at once.
• Command setenv can be used to initialize and update environment variables.
• Command unsetenv can be used to delete environment variables.
• Command clock -t x supported where x is the interval after which time will be printed on screen.(Can be terminated with Ctrl+C)
• Command remindme message t which would remind the user with 'message' after time t.
• Command pinfo <id> supported which prints out the process information of the process with pid 'id'
• Command echo can be used with double qoutes to preserve whitespaces.Moreover '\n', '\' and '"' are supprted too with echo.
• All the other basic shell commands are supported as they are.

Exit

quit