正则提取

ecjtubaowp

$str = 'Cpu(s):  4.2%us,  0.2%sy,  0.1%ni, 95.2%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st'

如何提取出95.2  ,就是后面有%id的那个。

试了好久。

sai9924

$str =~ m#(\d{1,2}.\d+\%id)#;

dgtnk

1. my ($capture) = $str =~ /([\d.]+)%id/;
   
2. print $capture;

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cdtits

zhu@ubuntu:~/perl$ perl reg.pl
95.2
zhu@ubuntu:~/perl$ cat reg.pl

1. $str = 'Cpu(s):  4.2%us,  0.2%sy,  0.1%ni, 95.2%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st';
   
2. $str =~ /.* (\d+.\d+)\%id/;
   
3. print "$1\n";

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zhu@ubuntu:~/perl$

cdtits

1. $str =~ /([\d+\.\d+]+)%id/;
   
2. print "$1\n";
   

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ecjtubaowp

Cpu(s):  4.2%us,  0.2%sy,  0.1%ni, 95.2%id,  0.2%wa,  0.0%hi,  0.0%si,  0.0%st

大家帮看一下，上面这个是用top获取的CPU值，然后提取，但是出不来：

1. perl -e 'my @cpuinfo = `top -n 1`;my ($cpu_line) = grep {/^Cpu/} @cpuinfo;my ($idle_load) = $cpu_line =~ /(\d+\.\d+)%id/;print $idle_load'

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不知是哪里错了。

jason680

回复 6# ecjtubaowp

try this one, you will see what happen
$ top -n 1 | head -3 | hexdump -C
...
000001f0  33 39 3b 34 39 6d 1b 28  42 1b 5b 6d 20 39 39 2e  |39;49m.(B.[m 99.|
00000200  34 25 1b 28 42 1b 5b 6d  1b 5b 33 39 3b 34 39 6d  |4%.(B.[m.[39;49m|
00000210  69 64 2c 1b 28 42 1b 5b  6d 1b 5b 33 39 3b 34 39  |id,.(B.[m.[39;49|
...

cdtits

1. top -n1 | grep -i 'cpu(s)' | cut -d, -f4 | cut -d% -f1

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ecjtubaowp

现在是要用perl搞,那个命令行是程序中的一部分。

yinyuemi

回复 9# ecjtubaowp


    use `top -n 1 -b`, instead of  `top -n 1`

-b : Batch mode operation
            Starts top in "Batch mode", which could be useful for sending out-
            put from top to other programs or to a file.