Re: read problem

[Greg Wooledge]

On Sun, Sep 25, 2022 at 03:44:35AM +0700, Robert Elz wrote:
> (in this message, \s represents a space, just for clarity - \s meaning space
> cannot be used in shells, any of them, anywhere)

Just for the record, if \s appears in the regex on the right hand side
of =~ in bash's [[ $string =~ $regex ]], it will be interpreted by the
regex engine in the system's libraries, and may or may not have a special
meaning.

unicorn:~$ regex='x\sy'
unicorn:~$ [[ 'x y z' =~ $regex ]] && echo match
match
unicorn:~$ cat /etc/debian_version 
11.5

It's not special to bash, of course -- just to the underlying regex
machinery on this platform (GNU libc).  Therefore, it cannot be used in
a script that's intended to be portable.