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I'm uncertain of how to do this with Regular Expressions and BASH. I have a long filename and a regex that matches part of the file name. How do i store the part of the file name i want?
Heres is some psuedo code that kind of explains what i want:
the regex was incompatible with sed. '{x}' does not repeat the previous pattern x times. its literally interpreted. In addition, with out the -n option sed displays all input. So sed wasn't making a match and was displaying all input lines.
This works:
echo $(echo $filename | sed s/^.*\([0-9][0-9][0-9][0-9]\).*$/\1/g)
As there is usually more than one way to skin a cat; is there a way to do this
1. in 1 line, like the way we did it w/ sed
2. have a more robust regex (i.e. have things like {x} at one's disposal)
As there is usually more than one way to skin a cat; is there a way to do this
1. in 1 line, like the way we did it w/ sed
2. have a more robust regex (i.e. have things like {x} at one's disposal)
i could have used grep -e (which is supposed to be the same as egrep, but some report egrep to be a crippled version of grep -e)
this would have worked as well:
echo $(echo $filename | grep -oE "[0-9]{4}")
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