sed字符串替换
[position]s/source/destination/flags
Position is optional。
一、S Specific Parameters
（1）&
| [nick@d01 bash]$ cat sedrep.txt w1 test my car [nick@d01 bash]$sed -e 's/w1/w2/g' sedrep.txt w2 test my car [nick@d01 bash]$sed -e 's/w1/&w2/g' sedrep.txt w1w2 test my car
|
（2）/n
| [nick@d01 bash]$ cat sedrep.txt w1 test my car [nick@d01 bash]$ sed -e 's//(test/)/(my/)/(car/)//2/3/1/' sedrep.txt w1 mycartest
|
Blue font string matchs “test my car”. And there are two blanks among/(test/), /(my/) and /(car/).
/(…./) is used to keep the value， which may be referenced by number index.
二、Flags Parameters
(1) g
replace in global space
| [nick@d01 bash]$ cat sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1 w1 w1 w1 [nick@d01 bash]$sed -e 's/w1/&w2/g' sedrep.txt w1w2 w1w2 w1w2 w1w2 w1w2 w1w2 test my car w1w2 w1w2 w1w2 w1w2 |
(2) number
replace the nth string in this line
| [nick@d01 bash]$ cat sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1 w1 w1 w1 [nick@d01 bash]$sed -e 's/w1/&w2/2' sedrep.txt w1 w1w2 w1 w1 w1 w1 test my car w1 w1w2 w1 w1 [nick@d01 bash]$ sed -e 's/w1/&w2/1' sedrep.txt w1w2 w1 w1 w1 w1 w1 test my car w1w2 w1 w1 w1w2 |
(3) p
replace the ith string in every line， and print out
| [nick@d01 bash]$ cat sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1 w1 w1 w1 [nick@d01 bash]$sed -e 's/w1/&w2/p' sedrep.txt w1w2 w1 w1 w1 w1 w1 w1w2 w1 w1 w1 w1 w1 test my car w1w2 w1 w1 w1w2 w1 w1 w1w2 w1w2 |
(4) w
write the result to one file
| [nick@d01 bash]$ cat sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1 w1 w1 w1 [nick@d01 bash]$ sed -e 's/w1/&w2/2w sedrep2.txt' sedrep.txt w1 w1w2 w1 w1 w1 w1 test my car w1 w1w2 w1 w1 |
三、Optional Position Parameter
| [nick@d01 bash]$ cat sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1 w1 w1 w1 w1 [nick@d01 bash]$sed -e '/car/s/w1/&w2/g' sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1w2 w1 w1 w1 w1 [nick@d01 bash]$sed -e '1,/car/s/w1/&w2/g' sedrep.txt w1w2 w1w2 w1w2 w1w2 w1w2 w1w2 test my car w1w2 w1 w1 w1 w1 [nick@d01 bash]$sed -e '/car/,3s/w1/&w2/g' sedrep.txt w1 w1 w1 w1 w1 w1 test my car w1w2 w1w2 w1w2 w1w2 w1 [nick@d01 bash]$sed -e '1,2s/w1/&w2/g' sedrep.txt w1w2 w1w2 w1w2 w1w2 w1w2 w1w2 test my car w1w2 w1 w1 w1 w1 |
sed -i write changes into file directly