每隔n插入一个字符

asdmusic

echo "adfsdfab" |sed  's/../ &/g'    每隔两个ad fs df ab


如果每隔20个  那 上面的  .  就是 20 ，但我不想输入20个点  是否可以类似   echo "adfsdfabasdfadsfasdfasdfasdfasdf3r234234234" |sed  's/.{20}/ &/g'


echo adfsdfabasdfadsfasdfasdfasdfasdf3r234234234 | sed 's/\(.\{4\}\)/ &/g'   最后还有部分没有拆分
adfs dfab asdf adsf asdf asdf asdf asdf 3r23 4234234   

关阴月飞

echo adfsdfabasdfadsfasdfasdfasdfasdf3r234234234 | sed 's/\(.\{4\}\)/ &/g'   最后还有部分没有拆分
adfs dfab asdf adsf asdf asdf asdf asdf 3r23 4234234   


echo adfsdfabasdfadsfasdfasdfasdfasdf3r234234234 | sed -r  's/.{4}/& /g'
adfs dfab asdf adsf asdf asdf asdf asdf 3r23 4234 234