Contents

getusage()

Usage:

getusage([Topic1,Topic2,...] [,file:FileName or orig:T or \
  alt:T, silent:T])
getusage(Pattern) where Pattern has form "part*", "*part", or "*part*".
getusage(key:KeyNames), where KeyNames is a CHARACTER vector or "?"

Keywords: general

getusage() is the function used by macro usage() to retrieve usage
information from a "help file", a text file in a special format.  It can
be used directly, but has the disadvantage that it searches only one
file.

getusage() searches only the "current" help file.  This is initially
"macanova.hlp" but can be changed by keywords 'file', 'alt' and 'orig'.

getusage() works identically to gethelp(), except it gives a only a
brief summary of the usage of commands, functions, and macros, instead
of full details.  On some general information topics such as 'options'
and 'graph_keys' it lists available items; on other general information
topics the usage is just a suggestion to read the full help.

getusage(...) is equivalent to gethelp(..., usage:T).

getusage(..., usage:F) is equivalent to gethelp(...).

getusage() returns an "invisible" LOGICAL scalar whose value is True
only when at least one topic requested was found.  The value may be
assigned or tested but will not be printed automatically.  See topic
'variables:"invisible"'.

getusage() scans only one help file.  See gethelp() for details.
Pre-defined macro usage(), used almost identically, scans all the files
named in CHARACTER vector HELPFILES.  See topic usage().

For many commands and macros, you can get more complete usage
information by help(topic, subtopic:"usage").

Prior to Version 4.12, getusage() was named usage().  usage() is now a
macro that uses getusage() to search several help files.  If you want
usage() to work identically to getusage(), you can define a simplified
version by:
  Cmd> usage <- macro("getusage($0)")

Prior to Version 4.11, topics longer than 12 characters
('transformations', for example) or that were control words ('if',
'while', 'for', 'else', 'elseif', 'break', 'breakall') had to be quoted.
This is no longer the case.

See gethelp() for full details.