问题
I'm taking the following structure from around the net as a basic example of how to read from a file in BASH:
cat inputfile.txt | while read line; do echo $line; done
My inputfile.txt is tab-delimited, though, and the lines that come out of the above command are space-delimited.
This is causing me problems in my actual application, which is of course more complex than the above: I want to take the line, generate some new stuff based on it, and then output the original line plus the new stuff as extra fields. And the pipeline is going to be complicated enough without a bunch of cut -d ' ' and sed -e 's/ /\t/g' (which wouldn't be safe for tab-delimited data containing spaces anyway).
I've looked at IFS solutions, but they don't seem to help in this case. What I want is an OFS...except that I'm in echo, not awk! I think that if I could just get echo to spit out what I gave it, verbatim, I'd be in good shape. Any thoughts? Thanks!
回答1:
Try:
cat inputfile.txt | while read line; do echo "$line"; done
instead.
In other words, it's not read replacing the tabs, it's echo.
See the following transcript (using <<tab>> where the tabs are):
pax$ echo 'hello<<tab>>there' | while read line ; do echo $line ; done
hello there
pax$ echo 'hello<<tab>>there' | while read line ; do echo "$line" ; done
hello<<tab>>there
来源：https://stackoverflow.com/questions/5127954/echo-changes-my-tabs-to-spaces