Normally it should be perl but other users told me that python is more useful, Personaly I used PERL, to start programming, I recommend you to read the book "Learning Perl" from Randal L.Schwartz,(O'reilly). Normally your perl file should look like this: (FOR YOUR CHANGE GEOMETRY SECTION) -------------------------------------------------------------- $file = $ARGV[0]; $largo = $ARGV[1]; $ancho = $ARGV[2]; $alto = $ARGV[3]; $angulo = $ARGV[4]; $base = $largo*$ancho; # Parse the perl sign pound (#) $val = "#"; # open up MYFILE for writing open(MYFILE,">$file"); #or die "Can't open up myfile: $file\n"; if we want the file to be readed! # now this line format will automatically apply to MYFILE format MYFILE = @<geometry of test_zonep defined in: ../zones/test_zonep.geo $val GEN test_zonep test_zonep describes a for testing in perl # type, name, descr 8 6 @###.### # vertices, surfaces, rotation angle $angulo @< X co-ord, Y co-ord, Z co-ord $val 0.00000 0.00000 0.00000 # vert 1 @###.##### 0.00000 0.00000 # vert 2 $largo, @###.##### @###.##### 0.00000 # vert 3 $largo, $ancho 0.00000 @###.##### 0.00000 # vert 4 $ancho .... CONTINUE ---------------------------------- and you can invoke it in linux by type: ./<a href="http://changegeo.pl">changegeo.pl</a> ARGV1 ARGV2 ARGV3 then for your SIMULATE option check the cookbook for runing espr in text mode. you can so do a for in a bash file, and then take out the value you are interested with "awk" (a language like perl) using this command: (FOR YOUR EVALUATE SECTION) awk '/Totals/ {print $2 "\n"}' prueba$i.cfg.wc_res.data > TOTAL then put your statement if Total == ValueYouWant Exit for and then voilà! :) Is a little bit rudimentary but I hope this could help you. Regards -- David GARCIA SANCHEZ ------------------------------------------------------------ Département Systèmes Énergétiques Environnement Ecole des Mines de Nantes 4, Rue Alfred Kastler 44300 Nantes France ------------------------------------------------------------ Email: <a href="mailto:david.garcia-sanchez@emn.fr">david.garcia-sanchez@emn.fr</a> Tel: +33 (0) 2 51 85 82 14 Mobile: +33 (0) 6 78 15 08 09 Fax: +33 (0) 2 51 85 82 99 ------------------------------------------------------------