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.
ADVERTISEMENTS
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
🐧 Get the latest tutorials on SysAdmin, Linux/Unix, Open Source/DevOps topics:
- RSS feed or Weekly email newsletter
- Share on Twitter • Facebook • 9 comments... add one ↓
UP NEXT
Bash Read Comma Separated CSV File on Linux / Unix
CentOS / Redhat Iptables Firewall Configuration Tutorial
Linux Network IP Accounting
Python Command Line Arguments Examples- psad: Linux Detect And Block Port Scan Attacks In Real Time
cat command in Linux / Unix with Examples
ip6tables: IPv6 Firewall For Linux
| Category | List of Unix and Linux commands |
|---|---|
| File Management | cat |
| Firewall | Alpine Awall • CentOS 8 • OpenSUSE • RHEL 8 • Ubuntu 16.04 • Ubuntu 18.04 • Ubuntu 20.04 |
| Network Utilities | dig • host • ip • nmap |
| OpenVPN | CentOS 7 • CentOS 8 • Debian 10 • Debian 8/9 • Ubuntu 18.04 • Ubuntu 20.04 |
| Package Manager | apk • apt |
| Processes Management | bg • chroot • cron • disown • fg • jobs • killall • kill • pidof • pstree • pwdx • time |
| Searching | grep • whereis • which |
| User Information | groups • id • lastcomm • last • lid/libuser-lid • logname • members • users • whoami • who • w |
| WireGuard VPN | Alpine • CentOS 8 • Debian 10 • Firewall • Ubuntu 20.04 |
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.