On Thu, Jul 06, 2006 at 10:41:55AM +0100, Jenny Hopkins wrote:

I'm trying to echo a command to a serial port that happens to require a "!". In order to send the command I need to escape the ! with a backslash. However, I'm finding that at the other end, the backslash stays there rather than being stripped off, so the received command is also escaped and therefore doesn't work.

Emulated on a terminal: I send jenny@phaedrus:~$ echo "\!tts MALE" > /dev/ttyp2 and receive \!tts MALE

But I need to receive !tts MALE

Any hints on how to acheive this?

Try single quotes: echo '!tts MALE' > /dev/ttyp2 J. -- Revd. Jonathan McDowell, ULC | I'm only here for the salad bar.

On Thu, Jul 06, 2006 at 10:41:55AM +0100, Jenny Hopkins wrote:

Hullo there,

I'm trying to echo a command to a serial port that happens to require a "!". In order to send the command I need to escape the ! with a backslash. However, I'm finding that at the other end, the backslash stays there rather than being stripped off, so the received command is also escaped and therefore doesn't work.

Emulated on a terminal: I send jenny@phaedrus:~$ echo "\!tts MALE" > /dev/ttyp2 and receive \!tts MALE

But I need to receive !tts MALE

That is because you quote the entire string. Quoting removes the special meaning of all characters (with the exception of $ in the case of double quoting), so the backslash in quotes represents a backslash character and is not interpreted as part of an escape sequence. So, either \!tts MALE or "\!tts MALE" will work as expected, but not both. Best regards, Jan -- +- Jan T. Kim -------------------------------------------------------+ | email: jtk@cmp.uea.ac.uk | | WWW: http://www.cmp.uea.ac.uk/people/jtk | *-----=< hierarchical systems are for files, not for humans >=-----*