Re: security considerations for: set x dir/[*] dir/*

2006-12-03, 21:36(+01), Michal Nazarewicz:
Lasse Kliemann <stu33404@xxxxxxxxxxxxxxxx> writes:

set x ${dir?}/[*] ${dir?}/*

is a usefull construct to prepare an iteration over all files in a
directory ${dir}, taking into account the cases where ${dir} is empty
or contains a file with name *. I suspect that one can also use --
instead of the x, but I am not sure.

The following steps for the iteration are:

shift &&
case "${1?} ${2?}" in
${dir?}/\[\*\]\ ${dir?}/\*) return 0 ;;
*) : ;;
esac &&
shift &&
while test "$#" -ge 1; do
{
# ... do something with $1 ...
shift
} || return "$?"
done

???

#v+
for FILE in "$dir/"*; do
[ -e "$FILE" ] || continue

You may want do use

[ -e "$FILE" ] || [ -L "$FILE" ] || continue

instead.

Note that OPs solution has the advantage to work even if you
don't have execute permission to the directory (but then, you
will not be able to do much with the files in that dir).

# ... do whatever you want with $FILE ...
done
#v-

or:

#v+
set -- "$dir/"*
while [ $# -gt 0 ]; do
[ -e "$1" ] || continue
# ... do whatever you want with $1 ...
shift
done
#v-



--
Stéphane
.

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