Read last line of file to check for value


 
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# 8  
Old 09-05-2008
The test command (aka [ -- really) is picky about its syntax. If the output from the backticks is the empty string, it will not see any argument at all where it expects one before the -eq. Either properly double-quote the backticks, or use a construct which is less brittle. Perhaps something like this:

Code:
if awk 'FNR == 1 { if (prevfile && prev !~ /^.{6}70/) { print prevfile; rc=1; } }
{ prevfile=FILENAME; prev=
END { if (prevfile && prev !~ /^/.{6}70/) { print prevfile; rc=1 } exit rc; }' $icofile; then
  : ... send to server
fi

# 9  
Old 09-09-2008
Have to admit to not following what you've coded above, so have stuck to the original, trying to "properly double-quote the backticks" - as follows.

for files in $icofile
do
if [ "tail -1 $icofiles | cut -c7-8" = "70" ]
then
echo "File correct format, has trailer..." >>$logfile
else
echo "File incorrect format, missing trailer..." >>$logfile
exit 2
fi
done
echo "Sending $icofile to AS400 ODIN" >>$logfile

Even though the file has '70' in positions 7/8, the script is dropping into the first 'else' (missing trailer).

Any ideas?

Last edited by daveaasmith; 09-09-2008 at 10:57 AM..
# 10  
Old 09-09-2008
Try:
VAR1=$(tail -1 $file | cut -c7-8)
#if [ "tail -1 $file | cut -c7-8" = "70" ]
if [ "$VAR1" = "70" ]
then
...

Last edited by vbe; 09-10-2008 at 06:04 AM..
# 11  
Old 09-09-2008
Your loop variable is "file" and the list of files it loops over is $icofile, yet you use $icofiles inside the loop; is this really correct?

You need both double quotes and backticks; you can break it up into a variable assignment with backticks and a comparison of the variable, like vbe suggests, or combine them:

Code:
if [ "`tail -1 $file | cut -c7-8`" = "70" ]; then ...

(assuming you really ought to be using $file rather than $icofiles in the command).
# 12  
Old 09-10-2008
Nice point era, I edited and corrrected also... didnt realize the typo change between the last and its previous post of daveaasmith...and I copied/pasted the last...
definitely $file (better than $files which is confusing whe taliking of one record...)
# 13  
Old 09-10-2008
Nice one folks. I have added the missing backticks (didn't realise these were also required, rather than the double quotes replacing them). I had indeed cut/pasted into this thread incorrectly (oops), but am now running the following, successfully:-

for files in $icofile
do
if [ "`tail -1 $files | cut -c7-8`" = "70" ]
then
echo "File correct format, has trailer..." >>$logfile
else
echo "File incorrect format, missing trailer..." >>$logfile
exit 2
fi
done
echo "Sending $icofile to AS400 ODIN" >>$logfile
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