bash 系の話だけど, $() とかバッククオートでコマンドを実行してその標準出力を得るさいに, そのままだと改行がなくなってしまう. そんな時は全体をダブルクオートでくくれば改行を残せる

$ echo $(ls -l /tmp/)
total 56 -rw------- 1 kosei wheel 849 12 7 09:13 Config-pAimbL -rw-r--r-- 1 kosei wheel 23020 12 4 22:40 debug.log drwx------ 4 kosei wheel 136 12 6 00:16 launch-8y9r7a drwx------ 3 kosei wheel 102 12 1 16:28 launch-O688DH drwx------ 3 kosei wheel 102 12 1 16:28 launch-Obe9Hd drwx------ 3 kosei wheel 102 12 1 16:28 launch-mH6LiV drwx------ 3 kosei wheel 102 12 1 16:28 launchd-156.GLXAJQ srwxrwxrwx 1 kosei wheel 0 12 1 16:29 mongodb-27017.sock drwxr-xr-x 67 kosei wheel 2278 12 4 22:53 please-sleep

bash-3.2$ echo "$(ls -l /tmp/)"
total 56
-rw-------   1 kosei  wheel    849 12  7 09:13 Config-pAimbL
-rw-r--r--   1 kosei  wheel  23020 12  4 22:40 debug.log
drwx------   4 kosei  wheel    136 12  6 00:16 launch-8y9r7a
drwx------   3 kosei  wheel    102 12  1 16:28 launch-O688DH
drwx------   3 kosei  wheel    102 12  1 16:28 launch-Obe9Hd
drwx------   3 kosei  wheel    102 12  1 16:28 launch-mH6LiV
drwx------   3 kosei  wheel    102 12  1 16:28 launchd-156.GLXAJQ
srwxrwxrwx   1 kosei  wheel      0 12  1 16:29 mongodb-27017.sock
drwxr-xr-x  67 kosei  wheel   2278 12  4 22:53 please-sleep