How to check for special characters in UNIX?

Question

I have a fixed width file with 10-15 columns. The file contains alphanumeric values. How do I check for any special characters (like !,@,#,$,% etc.) in the entire file in UNIX ?

there is a character class called punct .check for it. `[[:punct:]]`, may be it help. — P...., Oct 13 '16 at 12:40

Mustafa DOGRU · Answer 1 · 2016-10-13T13:25:08.510

1

try this;

grep -vn "^[a-zA-Z0-9]*$" yourFile

or

grep -vn "^[[:alnum:]]*$" yourFile

man grep :

-v, --invert-match Invert the sense of matching, to select non-matching lines.

-n, --line-number Prefix each line of output with the 1-based line number within its input file. (-n is specified by POSIX.)

[[:alnum:]] means the character class of numbers and letters in the current locale

edited Oct 13 '16 at 13:25

answered Oct 13 '16 at 13:00

Mustafa DOGRU

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You might want to allow whitespace as valid characters: `grep '[^[:alnum:][:blank:]]'` – glenn jackman Oct 13 '16 at 16:12

How to check for special characters in UNIX?

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