Maintaining Shell Scripts with make and SCCS

Although a shell script is a plain text file, it must have execute permission to run. Since SCCS removes execute permission for files under its control, it is convenient to make a distinction between a shell script and its "source" under SCCS. make has an implicit rule for deriving a script from its source. The suffix for a shell script source file is .sh. Even though the contents of the script and the .sh file are the same, the script has execute permissions, while the .sh file does not. make's implicit rule for scripts "derives" the script from its source file, making a copy of the .sh file (retrieving it first, if necessary) and changing the mode of the resulting script file to allow execution. For example:

$ file script.sh 
script.sh:				ascii text 
$ make script 
cat script.sh > script 
chmod +x script 
$ file script 
script:				commands text