Well first of all, look in cfengine_stdlib.cf - you might want to simply create a modified version of set_variable_values to do what you want (where you change the delimiter to "\s+" or something.
But more importantly, you have a fundamental misunderstanding of how edit_lines works. Here's basically what happens in a single edit_line bundle: 1) Cfengine makes a copy of the file you are editing 2) Cfengine makes all the edits in the COPY of the file (it tries to do it all in memory, so no file I/O) 3) After all edits (delete_lines, field_edits, insert_lines, replace_patterns), Cfengine sees if the new file is the same as the old one 4a) If no differences, delete the copy 4b) If differences, i) copy your original file to file.cfengine_before_edits, ii) rename the edited version to your filename In this way, there is no "window of opportunity". The file looks one way, and then suddenly looks a different way. You're safe! The problem exists when you have TWO bundles editing the same file - then there really is a window of opportunity between the two sets of edits. But if you use one edit_lines bundle, you're fine! -Dan On Oct 12, 2010, at 8:32 AM, no-re...@cfengine.com wrote: > Forum: Cfengine Help > Subject: Best practice in edit_lines > Author: pieterb > Link to topic: https://cfengine.com/forum/read.php?3,18695,18695#msg-18695 > > There a certain files where I want to make sure there is only one definition > of a certain attribute. For example, in /etc/nsswitch.conf, I want only one > instance of the line: "passwd ldap files". > > The way I currently do this is search the whole file, delete all entries that > start with passwd, and then add the right one again. This is to make sure > only that specific entry is in my nsswitch file. > > I feel however that this is a pretty dirty way to do this; there is a small > window in which there is nothing defined in the file (e.g., step one deleted > all lines starting with .., but not added the correct one yet) that makes me > a bit uncomfortable. > > How do you guys go about this? > > _______________________________________________ > Help-cfengine mailing list > Help-cfengine@cfengine.org > https://cfengine.org/mailman/listinfo/help-cfengine _______________________________________________ Help-cfengine mailing list Help-cfengine@cfengine.org https://cfengine.org/mailman/listinfo/help-cfengine
