strange character after ">>"

[chuikingman]

I use below bash script

#!/usr/bin/bash

top -n 1 -s | head -n 4 >> tmp.tmp
line=` cat tmp.tmp|wc -l `
echo $line
while [ $line -gt 0 ]
do
a=`cat tmp.tmp | head -n $line | tail -n 1 `
echo $a
echo $a >> tmp1.tmp
line=`expr $line - 1`
done

I vi the tmp.tmp and tmp1.tmp file and get strange character ....
how can I fix it ...

^[[H^[[2J^[[m^[(Btop - 17:49:08 up 19 min,  2 users,  load average: 0.09, 0.16, 0.28^[[m^[(B^[[39;49m^[[K
Tasks:^[[m^[(B^[[39;49m^[[m^[(B  74 ^[[m^[(B^[[39;49mtotal,^[[m^[(B^[[39;49m^[[m^[(B   1 ^[[m^[(B^[[39;49mrunning,^[[m^[(B^[[39;49m^[[m^[(B  73 ^[[m^[(B^[[39;49msleeping,^[[m^[(B^[[39;49m^[[m^[(B   0 ^[[m^[(B^[[39;49mstopped,^[[m^[(B^[[39;49m^[[m^[(B   0 ^[[m^[(B^[[39;49mzombie^[[m^[(B^[[39;49m^[[K
Cpu(s):^[[m^[(B^[[39;49m^[[m^[(B  0.6% ^[[m^[(B^[[39;49mus,^[[m^[(B^[[39;49m^[[m^[(B 10.8% ^[[m^[(B^[[39;49msy,^[[m^[(B^[[39;49m^[[m^[(B  0.0% ^[[m^[(B^[[39;49mni,^[[m^[(B^[[39;49m^[[m^[(B 81.1% ^[[m^[(B^[[39;49mid,^[[m^[(B^[[39;49m^[[m^[(B  7.3% ^[[m^[(B^[[39;49mwa,^[[m^[(B^[[39;49m^[[m^[(B  0.2% ^[[m^[(B^[[39;49mhi,^[[m^[(B^[[39;49m^[[m^[(B  0.0% ^[[m^[(B^[[39;49msi^[[m^[(B^[[39;49m^[[K
Mem: ^[[m^[(B^[[39;49m^[[m^[(B  2567708k ^[[m^[(B^[[39;49mtotal,^[[m^[(B^[[39;49m^[[m^[(B   391228k ^[[m^[(B^[[39;49mused,^[[m^[(B^[[39;49m^[[m^[(B  2176480k ^[[m^[(B^[[39;49mfree,^[[m^[(B^[[39;49m^[[m^[(B    44964k ^[[m^[(B^[[39;49mbuffers^[[m^[(B^[[39;49m^[[K
~
~
~
~
~
~
~
~
"tmp.tmp" 4L, 912C

[lomcevak]

By 'strange character' I assume you mean the '^[[H^[[2J^[[m^[('. Those are escape sequences that do things like clear the screen, position the cursor, etc. If you want just the text then add the '-b' option (batch mode) to the top command.

[Cabhan]

Indeed. The problem is that "top" does a lot of weird things, like erasing characters and clearing the screen. If you run top in a terminal, you will see that it updates itself, it does this by printing control characters, which have special meanings to a terminal. However, when printed to a file, they don't have special meanings, so they just appear.

As lomcevak says, using top's "-b" option will fix this. If we check the man page for top:

       -b : Batch mode operation
            Starts top in 'Batch mode', which could be useful for sending
            output from top to other programs or  to  a  file.   In  this
            mode, top will not accept input and runs until the iterations
            limit you've set with the '-n' command-line option  or  until
            killed.