A string is a sample (template) in SI - what is it?

Question

C++ / C#

A function is written to determine permissions by string int f(const char *str)
Hint: use the sample string "rwxrwxrwx" to parse the input string.
How can a string be used for parsing?
C program. Googling didn't help.
At the input of a string like:
"rwxr-xr-x"

Answer 1

rwxrwxrwx is the standard way to specify permissions on Posix systems (like Linux).
letters are decoded as "Read" "Write" "eXecute"
three sets - the first owner, the second group - all the others.
thus rwxr-xr-x means that the owner has rwx (all rights), the group has rx, the rest (who is not the owner and is not included in the specified group) have rx

Answer 2

The standard way to set permissions in a Unix environment.
owner/group/other
read - r/write - w/execute - x. If the appropriate right is not established, then -

Answer 3

You should return an int, where bit 0 is set if and only if the first character of the string matches the first character of the pattern, bit 1 is set when the second character of the string matches the second character of the pattern, and so on.
In the example, as far as I understand, you need to give a number equal to 101101111 in binary.