Terminal backslash input repeated in output I'm using zsh on a MacBook Pro, OS X 10.10. When I type in certain commands, such as this one:

cat myfile | awk -F $'\t' '{print $8, $9}' | sort | uniq -c | sort -k1,1n | awk '{if ($1 &gt; 50) sum += $1} END {print sum}'


, then part of the command is repeated before the actual output of the command. The output in this case looks like:

    " '{print $8, $9}' | sort | uniq -c | sort -k1,1n | awk '{if ($1 &gt; 50) sum += $1} END {print sum}' : myusername2525


Does anybody know how to get of the jumbled output? It kind of looks like a format string vulnerability or something similar to me.
The problem is the $ in the first awk statement in the chain:

awk -F $'\t' '{print $8, $9}'


The -F option for awk sets the record separator for your input. If you're really expecting the separator to be a dollar sign followed by a tab character you should move the dollar sign in to the single quotes like so:

awk -F '$\t' '{print $8, $9}'


Leaving the $ outside the single quotes means it's being interpreted by the shell as a variable reference. This is what's leading to your weird output. If you aren't expecting a dollar sign in the field separator, only a tab, change the awk call to:

awk -F '\t' '{print $8, $9}'


Based on what you've said, the above appears to be what you want.