If Then Else Statement not Working?

ep7network0819 · 10-31-2017, 07:21 PM

I cannot get my script to work using if-then-else statements. The script seems to always evaluate as true. Therefore, if the word Failed doesn't exist it still uploads a file to FTP server. I thought by using if-then-else statements the script will perform different computations depending on condition true or false. The script is designed to search for the word Failed, and if not found then close program and do nothing. The script seems to always evaluate as true, and as a result uploads file to FTP server whether the word Failed exist or not.

My script is below:

Code:

!/bin/bash

# Seach for word Failed
if find ~/Desktop -type f -name "*.log" -exec grep -l "Failed" {} \+
then
        # Enter FTP command to upload file to xxxxx
         HOST="x.x.x.x"
         USERNAME="xxxxx"
         PASSWORD="xxxxx"
        # Directory to pick up file
         FILE="~/Desktop/xxxxx.txt"

         # Login to remote server
         lftp $HOST <<END_SCRIPT
         user $USERNAME $PASSWORD
         cd xxxxx
         put $FILE
         bye
END_SCRIPT
else
         echo "Failed not found"
fi

Any suggestions in making my if-then-else statements work? The script runs without error, I think maybe the if-then-else
are wrong. Thanks for your time.

rknichols · 10-31-2017, 07:47 PM

The find command does not pass back the return code from a command run by "-exec". The only times find exits with a non-zero return code is if there is a syntactical error in its arguments, if a "-delete" action fails, or under the uncommon condition that a file disappears after its name has been read from a directory but before it can be processed.

Plus, your script does not actually do anything with the list of names returned by grep. It's not apparent just what you are trying to do. Perhaps you need to save that list of names in a variable. (Be careful doing that if there is any chance that the names might contain embedded space characters.)

Turbocapitalist · 10-31-2017, 11:37 PM

I see that GNU find 4.7.0 does pass an exit code based on -exec, but it would not be safe to rely on other versions of find acting that way. Perhaps a portable option would be to pass everything to xargs

Code:

find . -type f -print | xargs grep -l foo > files.txt; echo $?

But that does not address the FTP problem. FTP is not safe and cannot be made safe. So a priority ought to be made to remove it, and quickly. SFTP is part of the package OpenSSH-server and uploading can be automated through the use of keys and the batch mode.

ep7network0819 · 10-31-2017, 11:48 PM

Hi rknichols. Thanks for taking the time to reply to my post.

You mention

Quote:

Plus, your script does not actually do anything with the list of names returned by grep.

Well, one thing is for sure! If I run this line of code "find ~/Desktop -type f -name "*.log" -exec grep -l "Failed" {} \+" by itself, it locates the word failed and outputs the name of the file that contains the word failed. If the word failed doesn't exist, program ends.

ep7network0819 · 11-01-2017, 12:08 AM

At Turbocapitalist, It did not work.

Turbocapitalist · 11-01-2017, 12:09 AM

Quote:

Originally Posted by ep7network0819

At Turbocapitalist, It did not work.

What did not work?

MadeInGermany · 11-01-2017, 04:41 AM

For a reliable exit code you need to place the grep outside the find

Code:

if find ~/Desktop -type f -name "*.log" | xargs grep -q "Failed"
then

Or test the printed lines

Code:

if [ -n "$(find ~/Desktop -type f -name "*.log" -exec grep -l "Failed" {} +)" ]
then

pan64 · 11-01-2017, 05:57 AM

another approach:

Code:

if grep -l -R Failed ~/Desktop | grep -q '\.log$'; then
   do something
else
   echo not found
fi

NevemTeve · 11-01-2017, 07:56 AM

@OP: Let's assume you don't have white-spaces and special characters in your file-names. Then the start of your script should be like this:

Code:

FileList=$(find ~/Desktop -name '*.log' -type f | xargs grep -l -- 'Failed' | tr '\n' ' ')
if [ -n $FileList ]; then 
    echo "Do Something With $FileList (eg scp $FileList user@host:)"
fi

rknichols · 11-01-2017, 09:20 AM

Quote:

Originally Posted by ep7network0819

Well, one thing is for sure! If I run this line of code "find ~/Desktop -type f -name "*.log" -exec grep -l "Failed" {} \+" by itself, it locates the word failed and outputs the name of the file that contains the word failed. If the word failed doesn't exist, program ends.

That program ends regardless of whether anything was printed on the screen. Other than what you see on the screen, there is nothing to indicate whether or not the word was found. The return code is always zero, so there is nothing useful to test with "if ... ".

ep7network0819 · 11-08-2017, 10:06 PM

@pan64 and @MadeInGermany both your solutions worked. But when "Failed" isn't found echo command doesn't output "Failed not found". I tried putting echo command in a variable and it did not work.

Turbocapitalist · 11-08-2017, 10:43 PM

Quote:

Originally Posted by ep7network0819

I tried putting echo command in a variable and it did not work.

Again, what didn't work? Please show the exact code that is not working and be sure to remember to wrap it in [code] [/code] tags so that it is readable.