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Top Forums Shell Programming and Scripting if/else with an empty file... Post 302722733 by jim mcnamara on Sunday 28th of October 2012 12:09:54 PM
Old 10-28-2012
[[ ]] or [ ] act like "words" in shell. The word they almost exactly represent is "test".

So if you look up test documentation you find a lot of stuff you can test for.

Code:
 [  -s  /path/to/somefile ]

is the equivalent to
Code:
 test -s /path/to/somefile

and -s means 'Does the file exist and is the file size greater than zero (not empty)?'
! in front of the -s reverses the meaning because ! is the "not" operator.

Check out the other -[options] when you get a chance.
 

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wibble-test-genrunner(1)				      General Commands Manual					  wibble-test-genrunner(1)

NAME
wibble-test-genrunner - Code generator for wibble testsuites. SYNOPSIS
wibble-test-genrunner header <file> wibble-test-genrunner main <files> DESCRIPTION
The program generates .cpp files that are then compiled and linked into a test program for running tests from .test.h files. Examples of such .test.h files may be found among wibble headers, eg. /usr/include/wibble/regexp.test.h. In the first form, the program processes a single header file (usually of the form foo.test.h) and produces a corresponding .cpp file to be compiled. In the second form, it takes as <files> all the .test.h headers and produces a single main.cpp which contains the main() function of the test program, which then runs all the tests in all the .test.h files. The generated source code is always written to standard output and it is left up to the user to redirect it to a meaningful location. The program currently has no options other than the two forms above. The program is intended to be run as part of build process of programs or libraries using the wibble testing framework. For convenient use from CMake, there is a test.cmake script under /usr/share/wibble, that takes care of producing all the .cpp files (both per-header and the main one), compiling them and linking them into a single binary which executes the testsuite. AUTHOR
Petr Rockai <me@mornfall.net> wibble-test-genrunner(1)
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