Recently I ran into something I have seen before but never pursued an answer. I was testing a new (Bourne) shell script. I had the script open in my text editor. When I saved editing mods at a section that had not yet executred, while the script was running, the script would halt with an error. If I edited and saved changes in a section where the code had already executed then I had no problem.

I had always thought a script was launched or executed as a separate process. Apparently not so. Is there a way to concurrently edit and run shell scripts?

I'm using Slackware 12.2.

What editor were you using, and how are you starting execution on the script? I can't replicate the behavior you are talking about with Vim on my machine.

If I save the script and execute it, any changes I make while the script is running is ignored in the currently running script; they don't take effect until that process has ended and I start it again.

I'm using Kate, KDE 3.5.10.

I start the script in Konsole by typing the script name. The script is in the file search path, usually /usr/local/(s)bin.

bash interprtes and executes the script line by line. If you edit it during execution, then it loses track of the correct line just as you say. The whole file is not read into memory before beginning execution. For my large bash project, src2pkg, most of the is written as functions in many files which are first sourced with the execution not taking place till all functions are read. this means I can freely edit those files, even while the program is running.