How do convert tabs to spaces in a file using a bash shell?
You can use various tools. The expand command converts all tabs to spaces. It preserves backspace characters in the output; they decrement the column count for
tab calculations.
expand input.file > output.file expand data.txt > output.txt expand -t 2 data.txt > output.txt
The -t option can be used to set comma separated list of explicit tab positions. You can use the unexpand command convert spaces to tabs. See man page for more info:
man expand
man unexpand
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My imput.file looks like:
$ cat input.file
tux Linux
tux Linux
tux Linux
tux Linux
$
But executing expand on the file showing the same format(in STDOUT) as input.file…
$ expand input.file
tux Linux
tux Linux
tux Linux
tux Linux
$
Though I am getting the expected result with “tr” command.
I am using CentOS 5.3(x86_64); Any comment ?
That’s because expand expects 2 tabs (=8 charachter spaces) as default tab.
So it doesn’t a tab in your file.
The command expand -t1 wil work with your file, as t1 means 4 spaces
You can also use perl:
perl -pi -e ‘s/\t/ /’ file.name
:retab
for vim.
s are truncated in my posts itself :)
expand fails miserably on multibyte characters (i.e. on non-ASCII characters in UTF-8 encoding)
still as of coreutils 8.21 (2013)
Its working for me
Tab space conver into space
expand -t 2 file | mailx -s “xxxx” email@add.com
expand doesn’t seem to do the right thing.
Converting tabs to spaces in a piece of content is more than merely translating each tab character to a sequence of space characters. It needs to preserve the alignment of the text. So in this example text (no quotes):
“Foo\tBar\tBazinga!”
and with a tab spacing of 3 chars, the result should be (each period corresponds to a white space):
“Foo…Bar..Bazinga!”
This way the de-tabbed content would overlay the original content exactly (assuming the same tab setting).
Typo in my example, and not a great example. Let’s try this one instead:
“Foo\tBars\tBazinga!”
and with a tab spacing of 4 chars, the result should be (each period corresponds to a white space):
“Foo.Bars….Bazinga!”
Note how each tab char was not replaced with 4 spaces.