Check if file exists and whether it contains a specific string

Question

I want to check if file2.sh exists and also if a specific word, poet is part of the file. I use grep to create the variable used_var.

#!/bin/ksh  file_name=/home/file2.sh                   used_var=`grep "poet" $file_name`     

How can I check if used_var has some value?

Answer 1

Instead of storing the output of grep in a variable and then checking whether the variable is empty, you can do this:

if grep -q "poet" $file_name then     echo "poet was found in $file_name" fi 

============

Here are some commonly used tests:

   -d FILE           FILE exists and is a directory    -e FILE           FILE exists    -f FILE           FILE exists and is a regular file    -h FILE           FILE exists and is a symbolic link (same as -L)    -r FILE           FILE exists and is readable    -s FILE           FILE exists and has a size greater than zero    -w FILE           FILE exists and is writable    -x FILE           FILE exists and is executable    -z STRING           the length of STRING is zero 

Example:

if [ -e "$file_name" ] && [ ! -z "$used_var" ] then     echo "$file_name exists and $used_var is not empty" fi 

Answer 2

if test -e "$file_name";then  ... fi  if grep -q "poet" $file_name; then   .. fi