ploticus: controlling ploticus from other programs (automation)

## controlling ploticus from other programs (automation) | Welcome Gallery Handbook |
| Manual page for controlling_ploticus_from_other_programs_(automation)(PL)

## DESCRIPTION

Notes on executing ploticus under the control of another program in an automated way.``

## STRATEGY

As of version 2.00, pl can be directly invoked as a CGI program

A perl script which implements a web interface to ploticus was contributed by Tom McClure.``

Since it is a command-line program, ploticus can easily be invoked by other programs automatically for unattended use.`` For instance, web server CGI scripts can invoke pl to build PNG or GIF data displays on demand. Or pl may be invoked by cron to produce plots on a regular basis.``

The invoking program can build a ploticus script on the fly, or use one that has been created in advance.``

The actual invocation can be done using the equivalent of `system()`. For example, in C:

  `system( "pl -gif myfile.p ITEM=hgxz" );`

## VARIABLES

Variables may be useful for implementation of changeable paramters (the invoking program would execute pl and set variables on the command line).`` For example:

`pl -gif status.p STARTDATE=010198 ENDDATE=062699 GROUP=hgc`
data display engine
Copyright Steve Grubb

Markup created by unroff 1.0, `` `` December 10, 2002.