Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!tut.cis.ohio-state.edu!ucbvax!agate!shelby!decwrl!jumbo!hisgen
From: hisgen@jumbo.dec.com (Andy Hisgen)
Newsgroups: comp.unix.ultrix
Subject: csh echo problem with backquotes
Keywords: csh, echo, backquotes
Message-ID: <14174@jumbo.dec.com>
Date: 26 Oct 89 22:55:24 GMT
Organization: DEC Systems Research Center, Palo Alto
Lines: 69


I'm having a problem with csh's echo command in combination with back-quote.
The version of Ultrix we're running is 3.1, the csh is:

% ls -l /usr/bin/csh
-r-xr-xr-x  1 root        94208 Nov 15  1988 /usr/bin/csh

When I type the command:

% echo "`date` Start" > echoproblem

every other character in the output file is \377, according to od(1):
% od -c echoproblem
0000000  377   T 377   h 377   u 377     377   O 377   c 377   t 377    
0000020  377   2 377   6 377     377   1 377   5 377   : 377   1 377   3
0000040  377   : 377   4 377   7 377     377   P 377   D 377   T 377    
0000060  377   1 377   9 377   8 377   9 377     377   S 377   t 377   a
0000100  377   r 377   t  \n
0000105

This problem doesn't occur if I use /bin/echo instead of echo.  Nor
does it occur if I write:
% set d = `date`
% echo "$d Start" > echoproblem

Here are some more test cases, starting first with cases that have the
\377 problem followed by cases that don't have the problem.
These tests seem to show that if an echo command has an argument
that uses back-quotes, then any other arguments that are quoted
(whether with double-quotes, single-quotes, or backslash) have
a \377 stuck in front of each character.

% echo hello > hellofile
% echo "`cat hellofile` Start" | od -c
0000000  377   h 377   e 377   l 377   l 377   o 377     377   S 377   t
0000020  377   a 377   r 377   t  \n
0000027
% echo `date` "Start" | od -c
0000000    T   h   u       O   c   t       2   6       1   5   :   3   7
0000020    :   4   5       P   D   T       1   9   8   9     377   S 377
0000040    t 377   a 377   r 377   t  \n
0000050
% echo `date` 'Start' | od -c
0000000    T   h   u       O   c   t       2   6       1   5   :   3   8
0000020    :   0   0       P   D   T       1   9   8   9     377   S 377
0000040    t 377   a 377   r 377   t  \n
0000050
% echo `date` \Start | od -c
0000000    T   h   u       O   c   t       2   6       1   5   :   3   8
0000020    :   1   3       P   D   T       1   9   8   9     377   S   t
0000040    a   r   t  \n
0000044

Test cases that do not have the problem:
% echo `date` Start | od -c
0000000    T   h   u       O   c   t       2   6       1   5   :   3   9
0000020    :   0   3       P   D   T       1   9   8   9       S   t   a
0000040    r   t  \n
0000043
% echo `date` | od -c
0000000    T   h   u       O   c   t       2   6       1   5   :   3   9
0000020    :   2   8       P   D   T       1   9   8   9  \n
0000035
% 

Andy Hisgen
DEC Systems Research Center
hisgen@src.dec.com
DECSRC::HISGEN