unix tr查找并替换

Question

这是我在网上使用的标准网页上使用的命令.

tr '<' '\n<' < index.html

然而它给了我换行,但没有再添加背胡萝卜.例如

 echo "<hello><world>" | tr '<' '\n<'

回报

 (blank line which is fine)
 hello>
 world>

代替

 (blank line or not)
 <hello>
 <world>

谢谢

Answer 1

那是因为tr只有字符替换(或删除).

试试吧sed.

echo '<hello><world>' | sed -e 's/</\n&/g'

或者awk.

echo '<hello><world>' | awk '{gsub(/</,"\n<",$0)}1'

或者perl.

echo '<hello><world>' | perl -pe 's/</\n</g'

或者ruby.

echo '<hello><world>' | ruby -pe '$_.gsub!(/</,"\n<")'

或者python.

echo '<hello><world>' \
| python -c 'for l in __import__("fileinput").input():print l.replace("<","\n<")'