Re: use comm command with regular expression

[Bob Proulx]

e-letter wrote:
> File 1 contains data:
> /some/text/abcd.xyz
> 
> File 2:
> abcd.xyz
> 
> The manual does not seem to indicate that regular expressions can be
> used with 'comm'.

They can't be.  It doesn't make sense for comm.  Perhaps you should be
using 'grep' or 'sed'?

> The task is to be able to compare file1 to file2 using a regular
> expression as a criterion for comparison, such as:
> 
> *cd.xyz
> 
> Then create a new file 'file3' that contains only those lines that
> satisfy the regular expression, but must contain the same format style
> as in file1.

Sounds like a homework assignment.

> Any help please?

  $ grep -F cd.xyz file1 > file3

Or perhaps:

  $ grep -f file2 file1 > file3

But note that "*cd.xyz" doesn't make sense as a regular expression.
It looks like a file glob match instead.  Watch that string being used
for a regular expression carefully.  Perhaps "cd\.xyz" instead.

Good luck on working through your homework! :-)

Bob