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Exec FUe Pleplo;essor Page 1
Exec File Preprocessor
Overview
The exec file preprocessor supports a 1.111de variety of features for generating
exec files, inclUding parameterization (with defaults), prorrpting for input
and options, nested exec files, COITITenting, conditionals, general console IIO,
aroong others. These facilities should allol.ll you to create lOOdular.. flexible
exec files which are bOth pOlJlerful and easy to maintain.
Essentially the preprocessor provides a language interpreter for the
generation of IIJorKShop conmands. The basic operation of the exec preprocessor
is as follol.lls. The preprocessor is invoked when the workShop shell recognizes a
cornnand to run an exec file. The preprocessor then reads and processes its input
flle( s) and creates a teflllOrary file 1111th the output it generates (which
typically consists of WOrkShop directives and conmands to run other programs) .
This output file 1s then passed back to the I#OrKShOp Shell for execution. After
the execution of the conmands 1n the t~orary file haS terminated (either
having run to completion or having raised an error) the terrporary file is
deleted by the shell.
Execflle input consists of tlllO types of lines -- naI1lBl lines with conmands
lIIhiCh will be paSSed through to the workShop and e>eee COOII&1d lines whiCh are
directed to the preprocessor (and lIIhich w111 not get paSSed to the WOrkShop).
Thus, exec files actually are written in t\lO languages -- one directed to the
worKShop and any programs that may be run under the worKShop, and tne other
directed to the exec preprocessor i tself . So, I.IIhile the preprocessor has a