how to check string of character

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# 8  
Old 10-05-2007
Originally Posted by manas_ranjan
for your satisfaction....

[:alpha:] := all letters including digit too
I always thought the [:alnum:] character class included alphabets and digits.

Originally Posted by manas_ranjan
so i request you please go thru the query/questions.....where i clearly mentioned i need only character sets......even though my variable has alphanumeric/numeric/ i sud say please enter valid characters
I am signing off from this thread.
# 9  
Old 10-05-2007
thanx vino,

i tried another method , check this out,

for sample in abc 123 abc123
> do
> sample_test=`echo $sample | awk '/[[:digit:]]|[[: punct:]]/ { print -1}'`
> if [ "$sample_test" = "-1" ]
> then
> echo "$sample is not valid."
> else
> echo "$sample is valid."
> fi
> done

abc is valid.
123 is not valid.
abc123 is not valid.
# 10  
Old 05-12-2008
alpha-numeric valiation

if not work properly.
please try this. ++3+3 and 1-a4-- are valid.

#! /bin/ksh
for sample in -abc 123 abc123 ++3+3 1-a4--
sample_test=`echo $sample | awk '/[:digit:]|[: punct:]/ { print -1}'`
if [ "$sample_test" = "-1" ]
echo "$sample is not valid."
echo "$sample is valid."

Originally Posted by vino
When you face an issue, you show us what you tried, the error that you got and then we would be in a better shape to help you out.

Anyway, this should get you started.

[/tmp]$ cat
#! /bin/sh

for sample in abc 123 abc123
    if [[ $sample == *[[:alpha:]]* ]] ; then
        echo $sample
[/tmp]$ ./

I leave the rest to you as an exercise. Look under the section 'Pattern Matching' in the man pages of bash for other character classes.
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