Functions are a form of commands like aliases, and scripts. They differ from Korn shell scripts, in that they do not have to read in from the disk each time they are referenced, so they execute faster. They also provide a way to organize scripts into routines, like in other high-level programming languages. Since functions can have local variables, recursion is possible. Functions are defined with the following format:

function name { commands; }

Local function variables are declared with the typeset command within the function.

Function Commands

return return from a function
return n return from a function; pass back return value of n
typeset –f display a list of functions and their definitions
typeset +f display a list of function ...

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