Using read in bash without empty fields collapsing

Posted by Charles Duffy on Stack Overflow See other posts from Stack Overflow or by Charles Duffy
Published on 2011-01-07T03:49:55Z Indexed on 2011/01/07 3:53 UTC
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bash

I'm trying to read a multi-line tab-separated file in bash. The format is such that empty fields are expected. Unfortunately, the shell is collapsing together field separators which are next to each other, as so:

# IFS=$'\t'
# read one two three <<<$'one\t\tthree'
# printf '<%s> ' "$one" "$two" "$three"; printf '\n'
<one> <three> <>

...as opposed to the desired output of <one> <> <three>.

Can this be resolved without resorting to a separate language (such as awk)?

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Using read in bash without empty fields collapsing

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Related posts about bash

launching a program from bash causes bash to go to new prompt

How to debug a .bash_profile

Every command fails with "command not found" after changing .bash_profile?

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why is $0 set to -bash?

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