I'm not sure why my parse isn't working on this string. I got it to work by putting the ? after the .*, but I don't understand why the 1st parse isn't working. Here is the string and the 1st and 2nd parses.
my $string = "/usr/local/bin/python3.9 -u /usr/local/bin/scripts/master_program.py 4002 daily true 20230421";
my $pythonpgm = "master_program.py";
my ($midmark1) = $string =~ /.*$pythonpgm \d+ .*(\d+).*/;
my ($midmark2) = $string =~ /.*$pythonpgm \d+ .*?(\d+).*/;
print "\nmidmark1 => $midmark1\n";
print "\nmidmark2 => $midmark2\n\n";
This is the printout:
midmark1 => 1
midmark2 => 20230421
The .* matches everything it can. It would match up until the end of the string, but then the \d+ wouldn't match.
...master_program.py 4002 daily true 20230421
\_/\_______________/|\__/|\_________________/ XXX Wrong
| | | | | | X
| | | \ \ | |
.* $pythonpgm [ ] \d+ [ ] .* (\d+) .*
So it gives up one character to allow \d+ to match.
...master_program.py 4002 daily true 20230421
\_/\_______________/|\__/|\________________/||
| | | | | | | \
| | | \ \ | | \
.* $pythonpgm [ ] \d+ [ ] .* (\d+) .*
I'd use
/ \Q$pythonpgm\E [ ] \d+ [ ] .* [ ] (\d+) \z /xs
or just
/ \Q$pythonpgm\E [ ] .* [ ] (\d+) \z /xs
The space before the date acts as an anchor, forcing .* to backtrack further.