How to optimize this 2 lines of bash code

Question

I want to optimize a bash code using 1 line instead of two this is the lines i want to optimize:

grep -E "$name" /etc/passwd
if [ $? -eq 0 ]
     #...

so the if will test the exit of the last command (grep), i want to merge "grep -E "$name" /etc/passwd" in the if statement to have something like:

if [ ##### -eq 0 ]

thanks for your help :)

Vasily G · Accepted Answer · 2015-09-09 09:01:39Z

3

Without if:

grep "name" file && do_something

answered Sep 9, 2015 at 9:01

Vasily G

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user000001 · Accepted Answer · 2015-09-09 08:45:30Z

2

You can use the exit code of the command directly in the if statement:

if grep .... 
then
  echo "found"
else
  echo "not found"
fi

If you want to silence the output of the grep command you can add the -q option, and if you want to quit after the first match (saves time on large files) you can use -m 1.

answered Sep 9, 2015 at 8:45

user000001

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