On Saturday 22 March 2008 21:38:46 Nicholas Robinson wrote: > On Saturday 22 March 2008 21:18:11 Amadeus W.M. wrote: > > You would think specifying tab as a field separator for sort would work > > like this: > > > > cat file | sort -k 3 -t "\t" > > > > It doesn't: > > > > sort: multi-character tab `\\t' > > > > > > So after a little search and some trial and error I got this to work: > > > > cat file | sort -k 3 -t "`/bin/echo -e '\t'`" > > > > > > For my own curiosity, can someone please illuminate me as to why the > > first incantation does not work as expected? Is there a more natural way > > to specify \t other than echo? > > Take the double quotes out in your first attempt. So command becomes > > cat file | sort -k 3 -t \t > > Nick Sorry, I was a little bit quick off the mark. The \t doesn't yield a tab character (see below) as you were implying and I went along with in the first example! If you take the double quotes out as I suggested, then the field separator becomes the character t! I think (being a little more cautious this time!) that you want: \ followed by Ctrl V followed by Ctrl I If I remember correctly, sort interprets a tab as a default field separator anyway. As to the why: it is because the -t takes an argument which is a character. Putting double quotes around it stops the \ being elided and so \t as two characters \ and t are presented to sort which is expecting only one character. Hence its moan. Try echo "\t" and you will see what I mean. In my second attempt above, the Ctrl V stops the tab character (Ctrl I) being expanded on the command line and the \ joins the tab character to the t. HTH Nick
