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Full Discussion: How to use $variable in conditional sentences?
Top Forums Shell Programming and Scripting How to use $variable in conditional sentences? Post 302997607 by bakunin on Wednesday 17th of May 2017 08:41:52 AM
Old 05-17-2017
I think you mix up two different things: shell scripts and makefiles.

Makefiles (more precisely: the make-utility) work rule-based, so you don't need explicit conditionals - everything is a conditional anyway.

make works like that: you define so-called "dependencies" between files: i.e. you have three object files where each depends on a single source file. Whenever one of the source file changes the corresponding object file has to be generated anew. This is done by executing the code in the rule-definition. For every dependency you can create a rule, but usually you create rules for groups of dependencies: whenever ".c" (the source) changes, the corresponding ".obj" (the object) has to be generated and the rule for this is to call the compiler to compile exactly the one source-file. For this there are "make-variables" like "$@", "$<", etc., which are filled with the name(s) of the files involved in the rule. See the man-page of make for details.

You can also create cascades of these rules: you base .obj-files on .c-files and you base executables on the .obj-files. So, when a source file changes, the corresponding object is generated and in turn this leads to the executable being generated too (by calling the linker to link all the objects to the executable.

You might want to read this little introduction i once wrote.

I hope this helps.

bakunin
This User Gave Thanks to bakunin For This Post:
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LEARN ABOUT OSF1

style

style(1)						      General Commands Manual							  style(1)

NAME

       style - Analyzes surface characteristics of a document.

SYNOPSIS

       style [-ml] [-mm] [-a] [-e] [-l num] [-r num] [-p] [-P] file...

OPTIONS

       Displays  all  sentences  with their length and readability index.  Displays all sentences that begin with an expletive.  Displays all sen-
       tences longer than num.	Skips lists in the document.  Overrides the default -ms macro package.	Displays parts of speech of the  words	in
       the document.  Displays all sentences that contain a passive verb.  Displays all sentences whose readability index is greater than num.

DESCRIPTION

       The  style command analyzes the surface characteristics of the writing style of a document.  It reports on readability, sentence length and
       structure, word length and usage, verb type, and sentence openers. Because style runs deroff before looking at the text, formatting  header
       files should be included as part of the input.  The default macro package -ms may be overridden with the -mm option.  The -ml option, which
       causes deroff to skip lists, should be used if the document contains many lists that contain non-sentences. Use the other options to locate
       sentences with certain characteristics.

RESTRICTIONS

       Use of non-standard formatting macros may cause incorrect sentence breaks.

SEE ALSO

       Commands: deroff(1), diction(1)

																	  style(1)
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