UNIX for Dummies Questions & Answers

I am trying to write a bash script but do not know the unix commands I will have to use. I first have to test if an input file contains a number of characters.

For instance My input file's name is dunne.
cat dunne is bbcddceeceecbbacadce

So I want to test the out put of my file to see if it contains the characters abcde only.

if it does I will proceed with other commands,
if it does not, I will have to terminate.

I will appreciate any help on this.

Hi,
could U write the example in detail i.e Input file and desired output U want with performed operation.

ok Kaprus,

The input file(dunne) is a one line string without spaces eg:

bbcddceeceecbbacadce.

The script should test if these characters: 'a' 'b' 'c' 'd 'only are contained in the file(the characters may be repeated a number of times, doesn't matter).

If the input file contains string with only the characters 'a' 'b' 'c' 'd , then the script echo 'input file authentic'

if the file contains string with characters other than 'a' 'b' 'c' 'd then the script echo 'input file not authentic.

so if abbccddeebbd is input file

out put should be : input file authentic,

but if input file is abbgkfhccste

output should be: input file inauthentic

So the script should test if any input file contains string with only characters 'a' 'b' 'c' 'd

Thanks for your antcipated help.

this smells like homework stuff which is not allowed by our rules! i'll close this one down.