On 09/03/2013 07:56 PM, Herbert Xu wrote: > Harald van Dijk <harald@xxxxxxxxxxx> wrote: >> Hi, >> >> Now that Herbert fixed the reported crash in test (in a far simpler >> manner than I had suggested, which I like), I did some more testing, and >> came across one case that does not currently work, and did not work in >> the past, but is perfectly valid: >> >> $ src/dash -c 'test ! ! = !' >> src/dash: 1: test: =: unexpected operator > > Agreed. > >> $ src/dash -c 'test ! -o !' >> src/dash: 1: test: -o: unexpected operator > > Nope, the rule is quite clear that it only applies to binary > primaries, not operators. -o is an operator. Huh? http://pubs.opengroup.org/onlinepubs/9699919799/utilities/test.html states that there are only two operators "!" and "()", and specifically mentions that -a and -o are binary primaries: expression1 -a expression2 [OB XSI] [Option Start] True if both expression1 and expression2 are true; otherwise, false. The -a binary primary is left associative. It has a higher precedence than -o. [Option End] expression1 -o expression2 [OB XSI] [Option Start] True if either expression1 or expression2 is true; otherwise, false. The -o binary primary is left associative. [Option End] "test ! -o !" is a three-argument test, where $2 (-o) is a binary primary, so it is the binary test of $1 and $3, and the end result is an exit status of 0. Bash and ksh get it right, dash fails. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org
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