How to grep for the string if it is not followed by alphanumeric

Question

I need the below requirement

string123

stringsecond

string-third

-string-four

string_five

/string/

sixstring

this should not print

output

string-third

-string-four

string_five

/string/

So as per the output,the command should not grep string followed with alphanumeric only. I am using -w option with grep ,but it is eliminating underscore(_) strings also.

-w is removing the string_five also,but I have to grep that also — Rakesh Talari, Feb 02 '17 at 07:12
Something like `grep -v 'string[0-9a-zA-Z]' file` should solve it ` — Inian, Feb 02 '17 at 07:20
Thanks,its working good..but it can not handle "sixstring" what I added in the question. prefixed with alphanumeric also avoided.can we do that ? — Rakesh Talari, Feb 02 '17 at 08:30
I got a problem here,your command is printing the lines not having "string" also as per the output. I have to grep for lines having the string without prefixed and suffixed with alphanumeric — Rakesh Talari, Feb 03 '17 at 07:15

score 0 · Answer 1 · answered Feb 02 '17 at 07:12

0

Use a negated character class at the end of your regex.

If you're matching "string", then append a class like [^0-9a-zA-Z_] to the end.

answered Feb 02 '17 at 07:12

aghast

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How to grep for the string if it is not followed by alphanumeric

output

1 Answers1