Grep not working for string with both spaces and numbers

wackysiy1024 · 09-03-2020, 10:19 PM

Hi

I am trying to print all the following entries from my input file.

Quote:

pptstatistics#rtpRequestCount#path 0#rate
pptstatistics#rtpRequestCount#path 1#rate
pptstatistics#rtpRequestCount#path 3#rate
pptstatistics#rtpRequestCount#path 2#rate

Since my string had a space,I wrote the grep in following format

Quote:

grep "pptstatistics#rtpRequestCount#path *#rate " inputfile > output file

I wanted to get all the paths printed(in this case path 0-path 3)It didnt work. I also tried for another example string where i am trying to print the required strings with all paths and different cores. (essentially I am trying to print all with all different datapath and all values of icore

Expected output:

Quote:

datapath icore all parameter ocr-frames#datapath:0#icore:2
datapath icore all parameter ocr-frames#datapath:3#icore:5
datapath icore all parameter ocr-frames#datapath:5#icore:2

grep "datapath icore all parameter ocr-frames#datapath:*#icore:*" inputfile > output file

Any awk or sed commands to do this?

syg00 · 09-03-2020, 10:35 PM

You are likely confusing globbing and regex - you can't use the asterisk like that as a wildcard in regex. What happens if it isn't a number - do you care ?.

Replace the aster with a period (full-stop).

berndbausch · 09-03-2020, 11:59 PM

Quote:

Originally Posted by wackysiy1024

I wanted to get all the paths printed(in this case path 0-path 3)It didnt work.?

The asterisk in a regular expression matches a string of zero or more copies of the preceding character. Thus, "path *#" means the string "path", followed by zero or more spaces, followed by a hash sign. Therefore, none of the paths match this regular expression.

awk and sed are no different. For your purpose, grep is the right tool, but use syg00's advice.

pan64 · 09-04-2020, 03:14 AM

you might want to use an online regex tester like this: https://regex101.com/
it will not only allow you to test your expression, but also explain it

Turbocapitalist · 09-04-2020, 03:18 AM

Quote:

Originally Posted by syg00

You are likely confusing globbing and regex - you can't use the asterisk like that as a wildcard in regex.

See also "man 7 glob" about globbing versus "man 7 regex" and "man perlre" in addition to "man grep" for regular expressions.