[BusyBox 0001423]: [ ! a = b ] vs. [ a != b ]

[bugs at busybox.net]

The following issue has been SUBMITTED. 
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http://busybox.net/bugs/view.php?id=1423 
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Reported By:                jfree
Assigned To:                BusyBox
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Project:                    BusyBox
Issue ID:                   1423
Category:                   Standards Compliance
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     assigned
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Date Submitted:             07-05-2007 12:08 PDT
Last Modified:              07-05-2007 12:08 PDT
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Summary:                    [ ! a = b ] vs. [ a != b ]
Description: 
There is a discrepency (== error?) in ash's handling of the following:

ash
===
# [ ! a = b ]
# echo $?
1

# [ a != b ]
# echo $?
0


bash
====
$ [ ! a = b ]
$ echo $?
0

$ [ a != b ]
$ echo $?
0

On Thu, Jul 05, 2007 at 12:51:24PM -0400, Paul Smith wrote:
...
> According to the POSIX standard, this form is valid and ash's answer is
> wrong.
...
> This should be fixed in ash, because it's a bug... but I wonder why you
> just don't use the much more common (and hence more likely to work
> properly) "[ a != b ]"?

More info:

Regressing against i386 BusyBox v1.1.3 (Debian 1:1.1.3-4) :

        $ busybox [ ! a = b ]
        $ echo $?
        0

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Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
07-05-07 12:08  jfree          New Issue                                    
07-05-07 12:08  jfree          Status                   new => assigned     
07-05-07 12:08  jfree          Assigned To               => BusyBox         
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