I have a problem with bash/sh scripts that use subshells. Two sample shell scripts below, both with nested subshells, the first works and the second doesn't. The difference is that the logical 'and' (&&) is on the end of line one in the first but on the beginning of line two in the second faulty script. There is no whitespace after the '\' delimiter. The scripts execute just fine on a Solaris 2.8 box. Platform is RH ES 3.0 2.4.21-20.0.1, bash version is GNU bash, version 2.05b.0(1)-release (i386-redhat-linux-gnu). Is this a bug or expected behaviour? Any advice anyone out there can offer would be appreciated. Thx.

# cat /tmp/test1
((echo line1) && \
(echo line2))
# head -1 /tmp/test1 | od -c
0000000 ( ( e c h o l i n e 1 ) & &
0000020 \ \n
0000023
#
# cat /tmp/test2
((echo line1) \
&& (echo line2))
# head -1 /tmp/test2 | od -c
0000000 ( ( e c h o l i n e 1 ) \ \n
0000020
#
# bash /tmp/test1
line1
line2
#
# bash /tmp/test2
/tmp/test2: line 2: syntax error near unexpected token `'
/tmp/test2: line 2: `&& (echo line2))'

How about not using the \ at the end....

((echo line1)
&& (echo line2))

Same result. Still fails when '\' is removed from /tmp/test2:

# cat /tmp/test2
((echo line1)
&& (echo line2))
# sh /tmp/test2
/tmp/test2: line 2: syntax error near unexpected token `&&'
/tmp/test2: line 2: `&& (echo line2))'

Take a look at the parentheses: one unmatch open paren on the first line; one unmatched closes paren on the second. Try removing the unmatched paren from each line.

There are easier fixes than removing the unmatched parens. But I'm not after a fix, I'm trying to confirm if this is expected behaviour or a bug. IMHO, the '\' should tell bash the next line is a continuation of the previous line, so bash shouldn't report unmatched parens error. This is how it behaves under Solaris. The issue is not to find a workaround, we have lots. The question is whether or not this is a bug that the Linux community and Red Hat should fix or is it expected behaviour.

//

That's not the problem. The problem arises when running within a script. You essentially eliminated the problem by putting both subshells on the same line, which is not what we're after. I have all the fixes we need. We need to know if this should be fixed in bash. Need some high-level shell gurus to step in here.