Display statements during function execution
echo fcnname on
echo fcnname off
echo on all
echo off all
The echo command controls the display (or echoing) of statements in a function during their execution. Normally, statements in a function file are not displayed on the screen during execution. Command echoing is useful for debugging or for demonstrations, allowing the commands to be viewed as they execute.
The echo command behaves in a slightly different manner for script files and function files. For script files, the use of echo is simple; echoing can be either on or off, in which case any script used is affected.
echo on turns on the echoing of commands in all script files.
With function files, the use of echo is more complicated. If echo is enabled on a function file, the file is interpreted, rather than compiled. Each input line is then displayed as it is executed. Since this results in inefficient execution, use echo only for debugging.