编辑文本 sed -i 1i xyz test.txt 在第一行之前sed -i 1a xyz test.txt 在第一行之后插入sed -i 1c xyz test.txt 把第一行数据替换成xyzsed /^bb/i\kjdlfkjdslkf temp.txt //在匹配的行之前加入新一行sed /^bb/a\kjdlfkjdslkf temp.txt //在匹配的行之后加入
编辑文本 sed -i '1i xyz' test.txt 在第一行之前 sed -i '1a xyz' test.txt 在第一行之后插入 sed -i '1c xyz' test.txt 把第一行数据替换成xyz sed '/^bb/i\kjdlfkjdslkf' temp.txt //在匹配的行之前加入新一行 sed '/^bb/a\kjdlfkjdslkf' temp.txt //在匹配的行之后加入新行 sed -n '/xxx/w temp.txt' temp1.txt //temp1.txt中匹配xxx的行插入到temp.txt sed '/xx/c\sdfdsf' temp.txt //用新的一行数据替换匹配xx的行 sed '1d' t.txt /删除文件第一行 sed '/bro/d' t.txt //删除带bro的行 (实际修改,删除等加-i) sed '/^$/d' t.txt //删除空行 sed 's/^.*uid//' t.txt //将uid前这段字符替换成空,^第一个字符不能为*,要加.,另外在sed里字符与*连接要加. sed 's/night/NIGHT/' 1.TXT //将night替换 (加 -i 直接修改源文件1.txt,而不是将替换后的数据输出到屏幕) sed 's/night/NIGHT/g' 1.TXT 替换所有,不加g一行只替换一次 sed 's/.html//' b.txt >b0.txt sed 'y/bo/BO/' test.txt //将b替换成B,o替换成O sed 'y/bb ll/BB LL/' test.txt //将bb替换成BB,ll替换成LL 查询文本 sed '/he/w test1.txt' test.txt //读取test.txt内容匹配he的行写入test1.txt sed '1,2w test1.txt' test.txt //读取test.txt内容,第一二行写入test1.txt sed '/he/r test1.txt' test.txt //读取test.txt内容匹配he的行与test1.txt所有内容合并后输出 sed -n '1,3p' getrow.sh //显示一行到三行的肉容 sed -n '1,/hello/'p orig.txt //从第一行开始打印,打印到第一个含有hello行 //n的作用是取消默认输出 只打印包含模板的行,缺省为打印所有行(编辑和未编辑) sed -n '$p' getrow.sh //最后一行 sed -n '/echo/'p while.sh //打印包括echo字符的行 /pattern/模式 sed -e '/echo/=' while.sh //并且打印行号(并且整个文件都打印) -n 只打印实际行号 打印行号使用= sed -n -e '/dfs.support.append/=' hdfs-default.xml sed -n -e '/we/p' -e '/we/=' 2.txt //只打印匹配的行,并行显示行号 sed -n '/aa/=' aa.txt //只显示匹配上的行号 sed -n '/^h/'p test.txt //显示h为开头的行 sed '/^hello/d' test.txt //查询非某某开头的写法 sed -n '/s\{2,\}/'p test.txt //s字符至少匹配两次 sed -n '/[0-9]\{1,\}/'p test.txt //包含数字的行,用[0-9]+不支持 sed '2q' test.txt //打印到第二行退出 需要注意的是,sed并不直接操作初始数据,它操作的是一份原始数据的拷贝。sed处理时,把当前处理的行存储在临时缓冲区中,然后处理缓冲区中的内容,处理完成后,如果没有重定向到文件, 将把缓冲区中的内容送往屏幕,接着处理下一行直到处理完毕

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