How to match the first two characters in UNIX C shell?

[tony_taoyh]

During my setup of simulation environment,
I want to use UNIX C shell.

Now I have one variable:
set aa = "-- abcd efgh"

Then how to use C shell to decide the variable is strating with "--",
thanks a lot.

 

[nand_gates]

Here is an example script

#!/bin/csh -f
set aa = "-- abcd efgh" ;
echo $aa
if( "$aa" =~ --*) then
  echo "Match found";
else
  echo "No match";
endif

Hope this helps

 

[tony_taoyh]

Thanks a lot.

I will try it.

 

[tony_taoyh]

Yes, it can work...

The * in:
if ($line =~ --*) is important.

Thanks a lot.

Best Regards,
Tony

 

[rprince006]

Try to use perl, it is much more powerful for this kind of tasks.

Let me give you an example:

#!/bin/perl -w

use strict ;

my $filename = "yourfile";
my $outfile = "myoutputfile" ;

open(FH, "$filename") or die "cannot open $filename";
open(FHO, "$outfile") or die "cannot open $outfile";

while ( <FH> ) {

## Matching any patterns here!!

if ( /^--/ ) {
print "Pattern Matched.\n" ;

print FHO ""£%$£%" ; ## Put anything in your output file.
}
else {
print "Pattern did'nt match\n" ;
}
}

close FH ;

exit 0;

Regards,
rprince006

 

[ryang]

Yes, turn to perl please.
Csh is not fit for programming.

Search " Csh harmful programming" in google.You will get the answer why csh is not fit for progarmming