w*****n
发帖数: 94 | 1 THE BAD AND THE GOOD
I cringe anytime I see someone code inefficiently. Here are
three of the most common mistakes, followed by a better way to
do the same thing.
Bad: cat somefile | grep something
Better: grep something somefile
Why: You're running one program (grep) instead of two (cat
and grep).
Bad: ps -ef | grep something | grep -v grep
Better: ps -ef | grep [s]omething
Why: You抮e running two commands (grep) instead of three (ps
and two greps).
Bad: cat /dev/null > somefile |
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C********g
发帖数: 1548 | 2 sed -i '/AllowOverride None/c AllowOverride All' somefile
ubuntu/debian
这个起到什么作用？ |
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c**t
发帖数: 2744 | 3 我想在某个routine中将STDERR定向到文件，routine结束后，取消定向。
sub func
{
open(ERROR, "> somefile");
STDERR->fdopen(\*ERROR, "w);
...
close(ERROR);
}
问题是此后STDERR都消失了，怎么让它重新回到STDERR? |
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