grep exact word match (-w) does not work with file paths in a text file

Question

Im trying to grep for a filename with fullpath in a file which contains something like 'ls -l' output, but it fails to match it correctly.

Line in the shell script which does the string search

pcline=`grep -w "$file1" $file2` # grep for file1 in file2 contents

if i echo the command, the output of command looks like below

grep -w run /home/rajesh/rootfs.layout

Expected
lrwxrwxrwx 1 root root 3 Aug 28 run

Actual
lrwxrwxrwx 1 root root 7 Aug 28 bin/run-parts
lrwxrwxrwx 1 root root 3 Aug 28 run
-rwxr-xr-x 1 root root 303 Aug 28 tests/aes/run.sh
-rwxr-xr-x 1 root root 445 Aug 28 tests/auto_ui/run.sh
-rwxr-xr-x 1 root root 320 Aug 28 tests/available_memory/run.sh
-rwxr-xr-x 1 root root 308 Aug 28 tests/fonts/run.sh
-rwxr-xr-x 1 root root 309 Aug 28 tests/html_config_page/run.sh
-rwxr-xr-x 1 root root 361 Aug 28 tests/ipc/run.sh
-rwxr-xr-x 1 root root 304 Aug 28 tests/JSON/run.sh
-rwxr-xr-x 1 root root 303 Aug 28 tests/log4cplus_cpp/run.sh
-rwxr-xr-x 1 root root 301 Aug 28 tests/log4cplus_c/run.sh
-rwxr-xr-x 1 root root 751 Aug 28 tests/msm_basic/run.sh
-rwxr-xr-x 1 root root 472 Aug 28 tests/res_man_dependency/run.sh
-rwxr-xr-x 1 root root 465 Aug 28 tests/res_man_ipc/run.sh
-rwxr-xr-x 1 root root 789 Aug 28 tests/res_man_multi_process/run.sh
-rwxr-xr-x 1 root root 469 Aug 28 tests/res_man_private_client/run.sh
-rwxr-xr-x 1 root root 492 Aug 28 tests/res_man_public_client/run.sh
-rwxr-xr-x 1 root root 311 Aug 28 tests/virt_mem_config/run.sh
lrwxrwxrwx 1 root root 6 Aug 28 var/run]

The trick i tried is to add a white space, which is guaranteed in my input file, this works in console, but not when it is assigned to a variable.

grep " tests/aes/run.sh" /home/rajesh/rootfs.layout

Line in the script

pcline=`grep \"" $file1"\" $file2`     # grep for file1 in file2 contents

Please let me know if i have committed any errors in this script.

Answer 1

You can use egrep like this:

egrep "(^| )$file1( |$)" "$file2"

If file1="run" then above command will match string run preceded by line start or space and followed by space or line end.