regex

Shell Programming and Scripting
1

hi frnds
i m having prb while matching a numerical num...

[0-9]+ is not working for me... ( ?? )

so i m achieving the criteria with [0-9]\{1,\} ( pl suggest if i m wrong )

nw the prb is.. i dont want to match the number with all zeros in it..
eg 00000 or 0000000 etc etc...

pl help..

Thanks..
Anchal.

2

What shell are you using? Are these files? Are these patterns in a file? Are you using grep, awk, perl, sed, bash, tcsh?

3

hi
i am working on bash shell on linux box.
i am applying this pattern to search for files with some specific format...

pl help

4

Refer to the man page section on "Pattern Matching", otherwise known in Shell parlance as "fileglob". The [0-9] is right, but "+" doesn't work here. To match a non-zero digit followed by more digits, you need:

shopt -s nullglob
echo [1-9][0-9]*

If you can have leading zeros, but you don't want to match one with ONLY 0's, then you can do:

shopt -s nullglob
echo [1-9][0-9]*  [0-9]*[1-9][0-9]*  [0-9]*[1-9]

This last one matches : (1) any number starting with a non-zero, AND (2) any number with a non-zero in the middle, AND (3) any number ending with a non-zero.

The shopt -s nullglob ensures that if the expression does not match, you get the empty string (instead of the pattern itself).