CODEWITHSUNDEEP
linuxbash
user2494770
user2494770

Reputation:

Bash returning a no such file when file exists

I'm trying to run a grep command on a log file to grab a url to use for some functions. The problem is it keeps giving me a No such file or directory error whenever I try to run it. I thought this was bizarre so I prefixed it with an ls command to see if it did exist and lo and behold it is indeed there. Can someone tell me what the issue is, I have a feeling it's a syntax issue I'm not aware of but I can't figure it out.

#!/bin/bash

for i in `seq 1 3` ;
do
        ssh user@member${i}.domain.com << EOF
        cd /home/path/member${i}/logs
        ls #I've printed the output of this below
        test=$( grep -oP "http:.*microwebapp/$" "messages.log" )
        echo "Test variable = ${test}"
        exit
EOF
done

The output of the ls command is the below:

console.log
messages.log
status.log
trace.log

So I'm really confused about what's going on, I've also tried replacing "messages.log" with "./messages.log" to no avail.

EDIT: here's the full output for one iteration of the loop:

grep: ./messages.log: No such file or directory
Pseudo-terminal will not be allocated because stdin is not a terminal.
console.log
messages.log
status.log
trace.log
Test variable =

I suppose it's a little odd that the grep command throws an error before the ls command runs but I don't have an explanation for that either

Upvotes: 0

Views: 364

Answers (1)

glenn jackman
glenn jackman

Reputation: 246807

Because of your "plain" heredoc, these lines execute on your local machine, before the shell hands control to ssh

    test=$( grep -oP "http:.*microwebapp/$" "messages.log" )
    echo "Test variable = ${test}"

Try:

ssh user@member${i}.domain.com << EOF
    cd /home/path/member${i}/logs
    ls #I've printed the output of this below
    test=\$( grep -oP "http:.*microwebapp/$" "messages.log" )
    #....^
    echo "Test variable = \$test"
    #.....................^
    exit
EOF

By "plain" heredoc, I mean the terminating word is unquoted. One can put single quotes around the word, and that effectively single quotes the whole heredoc:

ssh remote_host <<'END'
#.................^...^
h=$(hostname)
d=$(date)
echo The time at $h is $d
END

You can't do that in your code because you rely on expanding the local var $i to change to the correct directory.

Upvotes: 6

Related Questions