Why do the execute bits need to be set?

Question

I have a simple python script that is writing data to a file in a log folder. The script is in /var/lib/cgi-bin and the log folder is in /var/lib/cgi-bin/logs. As the files in cgi-bin are executed by Apache or by me from the command line, the execute bits are set for both cgi-bin and files in cgi-bin.

However, when I try setting 666 on the cgi-bin/logs folder, the python script fails when I attempt to open a new log file to store data. If I set the permissions on cgi-bin/logs to 776, the script executes both from the command line and when a browser executes a file in cgi-bin.

Why does a folder that will only contain data need the execute bit set? Is it due to being inside a folder that must have the execute bits set?

Answer 1

I was thinking that a folder's permissions were inherited by the folder's contents which is incorrect.

Tkausl pointed out that execute permission on a folder doesn't mean the same thing that execute permission means on a file. For a folder, execute permission means the folder's contents may be viewed by the owner, group and/or all.

Linux uses a specific command, setfacl, to handle default file permissions.