Hello,
I observed today that a bash feature that used to work
in version 3.00.16(1) no longer works in version 3.2.25(1).
I have observed the bug on OpenSolaris snv_81 and Ubuntu
7.10 both of which run the same version 3.2.25(1).
In short the bug is the result of failure to expand the
subscript of an array if the subscript is a variable.
The following script should return a list of files with a
preceding (File <#>: ). However, it does not work that
way because the integer variable (${d}) used in the subscript
of the array statement (FileList[${d}]=${File}) does not get
properly expanded.
#!/bin/bash
declare -a FileList=('')
declare -i d=0
ls -1| while read File
do
FileList[${d}]=${File}
d=$((10#${d}+1))
done
d=0
while [[ ${d} -lt "${#FileList[*]}" ]]
do
echo "File ${d}: ${FileList[${d}]}"
d=$((10#${d} + 1))
done
I have found that this script works just fine with korn shell (ksh)
and bash version 3.00.16(1). Just not bash 3.2.25(1).
When I reviewed the COMPAT and CHANGES files, the only items
that looked remotely close to the problem that I have encountered
are the following:
bash-3.0-alpha/bash3.0-beta1:
l. When performing a compound array assignment, the parser doesn't
treat words of the form [index]=value as assignments if they're
the result of expansions.
bash-2.05b-alpha1/bash-2.05a-release:
jj. Array subscript expansion now takes place even when the array
variable is unset, so side effects will take place.
If I was a programmer, I would try to propose a fix but alas I am not.
The best I can do is provide a re-producible use case.
References:
http://tiswww.case.edu/php/chet/bash/COMPAT
http://tiswww.case.edu/php/chet/bash/CHANGES
Thanks in advance,
Brad
--
The Zone Manager
http://TheZoneManager.COM
http://opensolaris.org/os/project/zonemgr
