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1.6.1 The IDL HELP Command

Another HELP utility, which is part of IDL, displays current variables and their attributes, files and logical units that are open, and at what level you are within IDL (i.e.,the MAIN level, or inside a procedure). Simply type HELP at the IUE_IDL> prompt.

You may specify what information is to be displayed by adding arguments and/or keywords. If some keywords (e.g., system_variables) are used arguments will be ignored. Here are a few of the more common ways to use HELP:


gives a one line description of each variable listed,


gives a one line description of each open file listed,

help,/sys shows all system variables and their values,


shows the contents of each structure listed (e.g., system variable !P).

Only one keyword may be specified at a time. Positional parameters are optional. For example, help,/files will list all open files, and help,/struc will show the contents of all currently defined structures. See the IDL User's Guide for more information.