UNIX for Dummies Questions & Answers

Hi,

I am trying to write a script which will check if the filesize is grather than 0 KB, compress the file and send to the email list else if the file size is zero KB don't send a mail update the log

Code:

if [ `ls -l /tmp/file.txt | awk '{print $1}'` -eq 0 ]
then
echo "Validate the file" | mailx -s " There are errors : " ${EMAIL_LIST}
else
echo "No Errors" > log_file
fi

When I am executing the script I am getting the below error

Code:

 [: -rw-r--r--: integer expression expected

Please let me know where I am doing it wrong.

And if we compress the file and email, can we extract in windows using the normal winzip software?

Thanks and Regards,
Mora

Hello mora,

Kindly use as follows in if.

Code:

if [[ `ls -l /tmp/file.txt | awk '{print $1}'` -eq 0 ]]

EDIT: Also to check file size zero you can do as following.

Code:

if [[ -s /tmp/file.txt ]]

Thanks,
R. Singh

Thanks Ravinder for the quick reply, can you please tell me if we compress the file and send the file as attachemt can we unzip the file using winzip

Hello mora,

Yes we can do it, following link may help you to understand it more.

Information about WinZip and UNIX compress files - WinZip Computing :: Knowledgebase


Thanks,
R. Singh

The file size in ls -l output is field 5; not field 1. Try:
if [ `ls -l /tmp/file.txt | awk '{print $5}'` -eq 0 ]
but as RavinderSingh13 suggested (but I think he reversed the desired outcome), a much more efficient test is:

Code:

if [ ! -s /tmp/file.txt ]

Well, there are few "bugs" in your code.

Let's start with the reason why you're getting the error message.

In short: You are doing the comparison on the wrong field.

The awk command you used returns the first column ($1) from the output of ls -l /tmp/file.txt.

I illustrated the different fields below

Code:

-rw-rw-r-- 1 root root   60 Dec  1 20:41 file.txt
---------- - ---- ----   -- --- -- ----- --------
    $1     $2 $3   $4    $5  $6 $7  $8      $9

Note that the fields shown here might vary from system to system and thus it is no good practice to parse the ls -l output.

If you want to stick to your approach for whatever the reason, you need to change $1 in your awk command to $5, respectively to the field number that contains the file size on your system (verify in the shell first).

The second solution RavinderSingh13 has posted is probably the best alternative.

---

Another problem is that your code says if the filesize is 0, then send mail, but it should echo "No errors" if the filesize is 0.
So either you interchange the commands in the then and else section, or you change -eq to -gt

---

You are sending the email without attachment...

Below should zip the file and attach it to the email

Code:

zip /tmp/file /tmp/file.txt
echo "Validate the file" | mailx -s " There are errors : " -a /tmp/file.zip ${EMAIL_LIST}
rm /tmp/file.zip

When using zip, you should be able to unzip it on a windows machine.

Last but not least, maybe, before zipping the file, you will need to replace the UNIX/Linux newline character with Windows' equivalent using unix2dos (https://en.wikipedia.org/wiki/Unix2dos) or something, so that the text file can be properly displayed on Windows.