Word splitting with command substitution

Word splitting with command substitution

[Omari Norman]

% echo $(head -n 2 /etc/passwd)
root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/bin/sh

% contents=$(head -n 2 /etc/passwd)
% echo $contents
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh

Why does the second example give me two separate lines, while the
first is joined into one line? The zshexpn man page says that
unquoted command substitutions are split into words, so I would
think the first case is correct, but why does the second case work
as it does?

-- 
A new dinette set!

Re: Word splitting with command substitution

[Peter Stephenson]

Omari Norman wrote:
> % echo $(head -n 2 /etc/passwd)
> root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/bin/sh
> 
> % contents=$(head -n 2 /etc/passwd)
> % echo $contents
> root:x:0:0:root:/root:/bin/bash
> daemon:x:1:1:daemon:/usr/sbin:/bin/sh
> 
> Why does the second example give me two separate lines, while the
> first is joined into one line?

In the second case the assignment is to a scalar, so is necessarily a
single word, hence there is no splitting and the newlines are left
intact.  If you want multiple words, assign to an array:

contents=($(head -n 2 /etc/passwd))

-- 
Peter Stephenson <pws@csr.com>                  Software Engineer
CSR PLC, Churchill House, Cambridge Business Park, Cowley Road
Cambridge, CB4 0WZ, UK                          Tel: +44 (0)1223 692070


.