evap(2)

NAME
evap - evaluate C, Perl and Tcl command line parameters in a simple and consistent manner, type-check parameter values and provide complete command and parameter help (use in place of getopt and friends). evaluate_parameters can also be embedded in your application.

SYNOPSIS
See evap.c(2), evap.pl(2), evap.tcl(2) and evap_pac(2) for more information.

DESCRIPTION
All implementations of evaluate_parameters require certain information that you, an application developer, supply. At a minimum what is termed a Parameter Description Table (PDT) must be provided. A PDT is simply a data structure that describes a command's parameters and parameter aliases, their types and possible default values. Using the PDT as a guide, evaluate_parameters parses a user's command line, returning the results of the evaluation to the PDT structure for C programs, or to global variables for Perl and Tcl programs. Every command using evaluate_parameters automatically has a -help switch (alias -? for Tcl) which displays parameter help; no special code is required in your application. In fact, there are three levels of help: -usage_help, -help and -full_help. From a user's point of view, using C, Perl and Tcl programs with evaluate_parameters as the user interface is identical. Optionally, a help Message Module can be provided that gives the user additional command and parameter help. There are two auxiliary Perl programs which have proven very nice: generate_man_page and generate_tk_program. The Perl program generate_tk_program uses a command's full help output to create a Tcl/Tk X11 Motif GUI wrapper for said program. You must have Tcl 7.0 and Tk 3.3 or above. See the gentkp(1) man page for full details. Finally, the Perl program generate_man_page extracts all the nice command and parameter help information that you supply for an application and generates simple nroff output in the form of a man page. Keeping a progam's documentation accurate is thus simple and automatic. See the genmp(1) man page for full details.

FILES
For usage information refer to evap.c(2), evap.pl(2), evap.tcl(2) and evap_pac(2). See evap.h, evap.c, evap.pl and evap.tcl for complete and gory details on evaluate_parameters.

AUTHOR
Stephen O. Lidie, lusol@Lehigh.EDU Copyright (C) 1990 - 1994 by Stephen O. Lidie and Lehigh University. All rights reserved.

SEE ALSO
evap(2)
evap.c(2)
evap.pl(2)
evap.tcl(2)
evap_pac(2)
addmm,add_message_modules(1)
disci,display_command_information(1)
genmp,generate_man_page(1)
genpdt,generate_pdt(1)
genptkp,generate_tk_program(1)