bash sed - 将匹配传递给外部命令
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11719011/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
sed - pass match to external command
提问by kaefert
I have written a little script using sed to transform this:
我已经使用 sed 编写了一个小脚本来转换它：
kaefert@Ultrablech ~ $ cat /sys/class/power_supply/BAT0/uevent
POWER_SUPPLY_NAME=BAT0
POWER_SUPPLY_STATUS=Full
POWER_SUPPLY_PRESENT=1
POWER_SUPPLY_TECHNOLOGY=Li-ion
POWER_SUPPLY_CYCLE_COUNT=0
POWER_SUPPLY_VOLTAGE_MIN_DESIGN=7400000
POWER_SUPPLY_VOLTAGE_NOW=8370000
POWER_SUPPLY_POWER_NOW=0
POWER_SUPPLY_ENERGY_FULL_DESIGN=45640000
POWER_SUPPLY_ENERGY_FULL=44541000
POWER_SUPPLY_ENERGY_NOW=44541000
POWER_SUPPLY_MODEL_NAME=UX32-65
POWER_SUPPLY_MANUFACTURER=ASUSTeK
POWER_SUPPLY_SERIAL_NUMBER=
into a csv file format like this:
转换成这样的 csv 文件格式：
kaefert@Ultrablech ~ $ Documents/Asus\ Zenbook\ UX32VD/power_to_csv.sh
"date";"status";"voltage μV";"power μW";"energy full μWh";"energy now μWh"
2012-07-30 11:29:01;"Full";8369000;0;44541000;44541000
2012-07-30 11:29:02;"Full";8369000;0;44541000;44541000
2012-07-30 11:29:04;"Full";8369000;0;44541000;44541000
... (in a loop)
What I would like now is to divide each of those numbers by 1.000.000 so that they don't represent μV but V and W instead of μW, so that they are easily interpretable on a quick glance. Of course I could do this manually afterwards once I've opened this csv inside libre office calc, but I would like to automatize it.
我现在想要的是将这些数字中的每一个除以 1.000.000，以便它们不代表 μV，而是代表 V 和 W 而不是 μW，以便快速浏览时可以轻松解释它们。当然，一旦我在 libre office calc 中打开了这个 csv，我就可以手动执行此操作，但我想将其自动化。
So what I found is, that I can call external programs in between sed, like this:
所以我发现，我可以在 sed 之间调用外部程序，如下所示：
...
s/\nPOWER_SUPPLY_PRESENT=1\nPOWER_SUPPLY_TECHNOLOGY=Li-ion\nPOWER_SUPPLY_CYCLE_COUNT=0\nPOWER_SUPPLY_VOLTAGE_MIN_DESIGN=7400000\nPOWER_SUPPLY_VOLTAGE_NOW=\([0-9]\{1,\}\)/";'`echo 0`'/
and that I could get values like I want by something like this:
并且我可以通过这样的方式获得我想要的值：
echo "scale=6;3094030/1000000" | bc | sed 's/0\{1,\}$//'
But the problem now is, how do I pass my match "\1" into the external command?
但现在的问题是，如何将我的匹配项“\1”传递给外部命令？
If you are interested in looking at the full script, you'll find it there: http://koega.no-ip.org/mediawiki/index.php/Battery_info_to_csv
如果您有兴趣查看完整的脚本，可以在此处找到：http: //koega.no-ip.org/mediawiki/index.php/Battery_info_to_csv
回答by Kent
if your sed is GNU sed. you can use 'e' to pass matched group to external command/tools within sed command.
如果您的 sed 是 GNU sed。您可以使用“e”将匹配的组传递给 sed 命令中的外部命令/工具。
an example might be helpful to make it clear:
一个例子可能有助于澄清：
say, you have a problem:
you have a string "120+20foobar"now you want to get the calculation result of 120+20 part, and replace "oo" to "xx" in "foobar" part.
比如说，你有一个问题：
你"120+20foobar"现在有一个字符串，你想得到120+20部分的计算结果，把“foobar”部分的“oo”替换为“xx”。
Note that this example is not for solving the problem above, just for showing the sed 'e' usage
注意这个例子不是为了解决上面的问题，只是为了展示sed 'e'的用法
so you could make 120+20in the first match group, and rest in 2nd group, then pass two groups to different command/tools and then get the result. like:
所以你可以120+20在第一个比赛组中进行，然后在第二组中休息，然后将两组传递给不同的命令/工具，然后得到结果。喜欢：
kent$ echo "100+20foobar"|sed -r 's#([0-9+]*)(.*)#echo \|bc\;echo \| sed "s/oo/xx/g"#ge'
120
fxxbar
in this way, you could nest many seds one in another one, till you get lost. :D
通过这种方式，您可以将许多 sed 嵌套在另一个 sed 中，直到您迷路。:D
回答by Thor
As seddoesn't do arithmetic on its own I would recommend using awkfor something like this, e.g. to divide 3rd, 5th and 6th field by a million do something like this:
由于sed本身不进行算术运算，我建议将其awk用于类似的操作，例如将第 3、5 和 6 字段除以一百万，请执行以下操作：
awk -F';' -v OFS=';' '
NR == 1
NR != 1 {
/= 1e6
/= 1e6
/= 1e6
print
}'
Explanation
解释
-F';'and-v OFS=';'specify the input and output field separator.NR == 1pass first line through without change.NR != 1if it is not the first line, divide and print.
-F';'并-v OFS=';'指定输入和输出字段分隔符。NR == 1通过第一行没有变化。NR != 1如果不是第一行，则分割并打印。
回答by alinsoar
To divide by 1,000,000 directly, you do so :
要直接除以 1,000,000，您可以这样做：
Q='3094030/1000000'
sed ':r /^[[:digit:]]\{7\}/{s$\([[:digit:]]*\)\([[:digit:]]\{6\}\)/1000000$.$;p;d};s:^:0:;br;d'
