Software: libREV

Library for fake access to files from external app

Intercept open/stat system calls and substitute filename with original filename plus "-" and value of environment variable REV (if REV defined and such file accessible).

Usage: $ export LD_LIBRARY_PATH=/path/to/libREV/:$LD_LIBRARY_PATH $ export $ echo test1 > myfile.txt $ echo test2 > myfile.txt-experimental $ cat myfile.txt test1 $ REV=experimental cat myfile.txt test2

Usage example for apache. Set LD_PRELOAD before running apache, for example in runit/daemontools ./run file: exec env -i PATH=$PATH apache2 ... or in /etc/init.d/apache2: ${APACHE2} ${APACHE2_OPTS} -k start Also, if you use FastCGI for running your CGI scripts in separate daemon, you also should set LD_PRELOAD for that FastCGI daemon. Next, here is example of .htaccess configuration: RewriteEngine on RewriteRule ^-([^/]+)(/.*) $2 [E=REV:$1] SetEnvIf REDIRECT_REV (.+) REV=$1 !REDIRECT_REV PassEnv LD_PRELOAD