Hi there,

How can I run a script being sure that it runs all the way to the end even if the source file is deleted or replaced while running?
Actually, I have a script that runs daily on several servers. It replaces local files by updates from a master server. But I'd like it to replace itself too if an update is found on the master server.

Here is an example of what happens if a script is replaced while running:

~# cat script
echo statement 1
cp $0.update $0
echo statement 2
~# cat script.update
echo statement 3
cp $0.update $0
echo statement 4
~# bash script
statement 1
statement 4

it should be posible to replace a script while it is running withou any problem bcs the file is loaded into memory at execution time

Although I'm a newbie, I think the following code clearly shows that this is not the case:

~# cat script
echo statement 1
cp $0.update $0
echo statement 2
~# cat script.update
echo statement 3
cp $0.update $0
echo statement 4
~# bash script
statement 1
statement 4

Here is a solution that I found,
Tell me if this looks OK.

~# cat myscript
(( $inside )) || { inside=1; . "$0"; exit; }
echo statement 1
cp $0.update $0
echo statement 2
~# cat myscript.update
(( $inside )) || { inside=1; . "$0"; exit; }
echo statement 3
cp $0.update $0
echo statement 4
~# myscript
statement 1
statement 2
~# myscript
statement 3
statement 4