>>>>> Glynn Clements <[EMAIL PROTECTED]> writes:
>>> Also the "for MAP in ``" method would need to be changed if there
>>> are thousands of maps?
>> I don't think so. Since the `for' command is internal to the Shell,
>> there's no command line to be passed to any other process, and so
>> there're no command line length limits in force.
>> Still, using COMMAND | while read VARN ; do ...; done looks more
>> clean to me.
> The while/read approach saves keeping the list of maps in
> memory. Once upon a time, that might have mattered; with modern
> systems, you would need millions of maps before it became an issue.
``while read'' saves one from using one level of backquotes,
thus, in my opinion, making the code a bit more readable.
Consider:
for r in `g.mlist pattern="example-\`date +%Y-%m-%d\`-*"`; do
...
done
g.mlist pattern="example-`date +%Y-%m-%d`-*" | while read r; do
...
done
Besides, the body of a ``while read'' loop is executed ``in
parallel'' to the command to the left of the pipe. On the
contrary, the ``for'' pattern will wait until the command inside
of the backquotes completes.
There're whitespace issues, though hardly relevant to the
`g.mlist' case.
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