tchrist@convexe.uucp (Tom Christiansen) (10/26/89)
here's one that prints out its input in multi-column format.
hah, you say, pr already does that! true, but pr uses a
column-major order and this (i call it "words") does so in
a row-major one. to see what i mean, compare:
% ls
% ls | pr -l1 -t -5
% ls | words
note lines 1 and 3 produce the same output, but you can't massage
pr into doing this. in other words, (`ls -1 | words`) eq (`ls -C`).
it shows a good use of indexed arrays, as well as more dynamic
code generation via sprintf and eval. it derives your current cols
from your termcap entry. i could have read from the output
of stty, but that's slow, or i could have used the ioctl()
from perl3, but i that's system dependent. this will work
with perl2.
--tom
#!/usr/local/bin/perl -w
sub eol { ($elt+1) % $cols == 0; } # is this the last elt on line?
$maxlen = 1; # widest string yet seen
$cols = ($ENV{"TERMCAP"} =~ /:co#(\d+):/) # parse termcap
? $1 # from termcap if found
: 80; # else default to 80
while (<>) { # read stdin into $_
s/\s+$//;
$maxlen = $mylen if (($mylen = length($_)) > $maxlen);
push(list, $_);
}
$maxlen += 1; # spaces
$cols = int($cols / $maxlen);
$rows = int(($#list+$cols) / $cols);
$mask = sprintf("%%-%ds ", $maxlen);
for ($elt = 0; $elt < $rows * $cols; $elt++) {
$target = ($elt%$cols) * $rows + int(($elt/$cols));
$piece = sprintf($mask, $target < ($#list+1) ? $list[$target] : "");
$piece =~ s/\s+$// if do eol(); # don't blank pad to eol of line
print $piece;
print "\n" if do eol();
}
print "\n" if do eol();
Tom Christiansen {uunet,uiucdcs,sun}!convex!tchrist
Convex Computer Corporation tchrist@convex.COM
"EMACS belongs in <sys/errno.h>: Editor too big!"