Does anybody have a good means for reviewing output from long
(multi-screen) YUM sessions? Less -r almost works.
The problem:
Yum writes lines that look normal but are actually composed of strings
which keep rewriting the same line as the data changes. These strings
are separated by ^M which causes the cursor to go back to the
beginning of the screen line to rewrite the entire line with updated
data. This is how it gets those counters to increment and the row of =
or # to keep getting longer.
For example, using fictitious data off the top of my head:
Extras 1% 1/1586^MExtras 1% 2/1586^M...^MExtras 100% 1586/1586
Add to that the counter during download of each new package to be
installed and you have a combination of very long lines and lots of
them. I have output from a few days ago whose maximum line length is
3547 and whose line count is 442.
What I want to do is review this output from the top without having to
read each of these ^M-separated strings.
Fedora includes a utility called script(1) which captures the lines as
they're sent to the screen. In fact, it's from a script log that the
example above is patterned. So, I can get the output into a file. But
how to display it?
less -r almost works. -r causes the ^M's to be executed, so each such
line displays its final incarnation (the 100% 1586/1586 counter in the
example).
The only problem here is that there's also one or more lines which
must be folded. The -r switch in less causes it to not attempt keeping
track of folded lines. This can cause paging to scroll some unviewed
lines off the top of the screen. I recently went from item 35 at the
bottom of one page to 46 at the top of the next. I can move forward
and back a line at a time with the arrow keys but it's a pain and may
not always suffice.
I have a very thorough text display script set (lb) that I use all the
time. I thought I would use grep to locate the last ^M or 3 in each
line; but the lines are sometimes too long for grep.
There are all kinds of things that might help, like fold or col for
example, but I was wondering if anyone has actually used these for
this purpose. There's a utility called scriptreplay that I haven't
located yet. And of course a C programmer could probably knock
something together in no time (hint hint :-).
Thanks in advance for any info, especially personal experience,
--
Lee Maschmeyer
<lee_Maschmeyer@xxxxxxxxx>
"The rain has turned to tears,
And I've been achingly, agonizingly empty these many years...
And I've only had two beers."
--Bob and Ray
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