topic Re: Echo and backslash in Operating System - HP-UX

Echo and backslash

Leo The Cat — Fri, 12 Sep 2008 12:22:05 GMT

Hi

I'd like to produce the echo below:

123\\abc

I've tried echo "123\\abc" or "123\\\\abc"without succes !

Any Idea ?

Regards
Den

Re: Echo and backslash

James R. Ferguson — Fri, 12 Sep 2008 12:26:46 GMT

Hi Den:

echo "123\\\\\\\\abc"
123\\abc

Regards!

...JRF...

Re: Echo and backslash

Steven Schweda — Fri, 12 Sep 2008 12:35:11 GMT

dy # echo '123\\abc'
123\\abc

dy # echo "123\\\\abc"
123\\abc

dy # uname -a
HP-UX dy B.11.11 U 9000/785 2012616114 unlimited-user license

Of course, that's using bash. With /bin/sh,
it seems to be harder.

dy # echo "123"'\\\\'"abc"
123\\abc

Re: Echo and backslash

OldSchool — Fri, 12 Sep 2008 13:11:41 GMT

in "sh"

echo "123\\\\\\acb"

works as well.

Re: Echo and backslash

James R. Ferguson — Fri, 12 Sep 2008 13:18:27 GMT

Hi (again) Den:

> Steven: Of course, that's using bash. With /bin/sh, it seems to be harder.

...and without rancor, I would have to say that since this is HP-UX it's fair to assume that we should be using the *standard* HP-UX shell ('/usr/bin/sh' or '/sbin/sh'). The bash shell's handling of backslashes in its implementation of 'echo' differs significantly.

On an 11.11 machine:

# echo ${SHELL}
/sbin/sh
# echo "123\\abc"
123bc
# echo "123\\\\abc"
123\abc
# echo "123\\\\\\\\abc"
123\\abc

Regards!

...JRF...

Re: Echo and backslash

Leo The Cat — Fri, 12 Sep 2008 14:01:06 GMT

Thanks !

Re: Echo and backslash

Steven Schweda — Fri, 12 Sep 2008 14:26:32 GMT

> ...and without rancor, I would have to say
> that since this is HP-UX it's fair to
> assume that we should be using the
> *standard* HP-UX shell ('/usr/bin/sh' or
> '/sbin/sh').

Assume what you wish, but "should" is your
opinion. Bash runs on HP-UX, too, however.

> The bash shell's handling of
> backslashes in its implementation of 'echo'
> differs significantly.

No argument there.

> # echo ${SHELL}
> /sbin/sh

Not a good test.

dy # echo "123\\\\abc"
123\\abc
dy # echo $SHELL
/sbin/sh

SHELL is not guaranteed to agree with the
current shell.

Re: Echo and backslash

Dennis Handly — Sat, 13 Sep 2008 01:49:06 GMT

Basically should should treat backslash as a character only to used to quote other chars. :-)

One thing about quoted strings, you'll need to double up backslashes in "" vs ''.
So one would think that this would work:
echo "123\\\\abc"
echo '123\\abc'

Unfortunately this doesn't work because echo then has its own rules about backslashes.