----------------- myShell Tutorial ----------------- * Preface --------------------------- This is a simplified shell. It will perform a set of inbuild commands and will outsource all other commands to the external shell. * Command Syntax --------------------------- The commands below follow a specific syntax. The syntax is as follows: Command: <command> [arg1 arg2 ... argN] [< inputArg] [>|>> outputArg] [&] [ ] - square brackets represent optional arguments | - piping symbol "|" means that either one of the args listed must be used. < > - angle brackets represent mandatory arg > | >> : represents output redirection from stdout to a file - > appends to end of given file - >> rewrites whole file with output < : represents input redirection from user input to a given file & : represents background execution of a command * Input and Output redirection ------------------------------------------- As described in the syntax section above, I/O redirection allows users to either move the results from a command to a file (output redirection) or instead of giving written commands, use a file to input those (input redirection). See Command Syntax section to see how to use I/O redirection. * Background Execution ---------------------------------- Background execution allows users to run commands in the background while still being able to feed other commands into the simpleshell. The syntax for this can be found in the Command Syntax section of this help file. * Change Directory <cd> --------------------------- Allows you to change a directory. Type "cd .." to back a directory. To get the current directory type "cd". Syntax: <cd> [args] * List Directory <dir> --------------------------- Lists the contents of a given directory Syntax: <dir> <arg1> [>|>> outputArg] * Env Variables <environ> --------------------------- List all environment variables Syntax: <environ> [>|>> outputArg] * Printing Strings <echo> --------------------------- Print out any string onto terminal. Syntax: <echo> [arg1 ... argN] [>|>> outputArg] * Help File <help> --------------------------- To view this help file type "help". But you already know that don't you? Syntax: <help> [>|>> outputArg] * Pause Shell <pause> --------------------------- Pause the shell from running. Once you type this command press ENTER to continue Syntax: <pause> * Clear Screen <clear> --------------------------- Clear the screen of previous output. Syntax: <clear> * Quit Shell <quit> --------------------------- Quit the shell. Syntax: <quit> * Other Commands --------------------------- All external commands can be run with the following syntax. Syntax: <command> [arg1 arg2 ... argN] [< inputArg] [>|>> outputArg] [&]