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How to selectively suppress perl output?

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Top Forums Shell Programming and Scripting How to selectively suppress perl output?
# 8  
Old 01-30-2012
Quote:
Originally Posted by LessNux
...
Code:
#!/bin/bash
set -f
vLn='bb cc dd'
echo $vLn | \
perl -pe 'my @vAry = glob; foreach my $i (@vAry) {print "$i\n";}'

...
I would like the entire perl statement to output the following.
bb
cc
dd

However, the actual output from the entire perl statement is
bb
cc
dd
bb cc dd

How can one suppress the output from the first perl substatement?
...
Are you okay with removing the "p" switch?
It's similar to the "n" switch, but it prints the input line by default (similar in function to the "p" switch of sed).

For example, if your shell script were like so -

Code:
$
$
$ cat -n bash_to_perl.sh
     1  #!/bin/bash
     2  set -f
     3  vLn='bb cc dd'
     4  echo $vLn | \
     5  perl -pe ''
$
$

then the output will be the value of $vLn, even when you are doing nothing in your Perl one-liner -

Code:
$
$ cat -n bash_to_perl.sh
     1  #!/bin/bash
     2  set -f
     3  vLn='bb cc dd'
     4  echo $vLn | \
     5  perl -pe ''
$
$
$ ./bash_to_perl.sh
bb cc dd
$
$

If you use the "n" switch instead, then -

Code:
$
$
$ cat -n bash_to_perl.sh
     1  #!/bin/bash
     2  set -f
     3  vLn='bb cc dd'
     4  echo $vLn | \
     5  perl -ne 'my @vAry = glob; foreach my $i (@vAry) {print "$i\n";}'
$
$
$ ./bash_to_perl.sh
bb
cc
dd
$
$

tyler_durden
This User Gave Thanks to durden_tyler For This Post:
LessNux
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