如何找到最后一行带有“错误”的日志文件的名称？

Question

I am trying to find the id's of jobs that end in error.

When I use

for i in *log
do tail -n 1 $i | grep error
echo $i
done

It seems to find error on the last line of each file, even for files that don't have errors on the last line, and returns all of the filenames with

STOP fatal_error
out1.log
STOP fatal_error
out2.log
STOP fatal_error
out3.log
....

even though

grep error out1.log 

returns nothing

Alternatively, is there an easier way to get a list of the jobs that end in error? I tagged with qsub because I use qsub to submit the jobs

Answer 1

You need an if statement so that you only echo the filename when the grep succeeds:

for i in *.log
do  
    if tail -n 1 $i | grep error > /dev/null 
    then 
        echo $i
    fi  
done

Also, redirect the grep results to /dev/null so it doesn't appear in the output.

Answer 2

You want to say

do tail -n 1 $i | grep error

not

do tail -n 1 *.log | grep error

Otherwise, you are checking every log file at every iteration and will always get the same results.

Answer 3

Your logic is incorrect. echo $i will have the listing of the file, not the grep output