1、使用重定向的方法
[[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# > test.txt [[email protected] ~]# du -h test.txt 0 test.txt
2、使用true命令重定向清空文件
[[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# true > test.txt [[email protected] ~]# du -h test.txt 0 test.txt
3、使用cat/cp/dd命令及/dev/null设备来清空文件
[[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# cat /dev/null > test.txt [[email protected] ~]# du -h test.txt 0 test.txt
################################################### [[email protected] ~]# echo "Hello World" > test.txt [[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# cp /dev/null test.txt cp:是否覆盖"test.txt"? y [[email protected] ~]# du -h test.txt 0 test.txt
################################################## [[email protected] ~]# echo "Hello World" > test.txt [[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# dd if=/dev/null of=test.txt 记录了0+0 的读入 记录了0+0 的写出 0字节(0 B)已复制,0.000266781 秒,0.0 kB/秒 [[email protected] ~]# du -h test.txt 0 test.txt
4、使用echo命令清空文件
[[email protected] ~]# echo "Hello World" > test.txt [[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# echo -n "" > test.txt ==>要加上"-n"参数,默认情况下会"/n",也就是回车符 [[email protected] ~]# du -h test.txt 0 test.txt
5、使用truncate命令清空文件
[[email protected] ~]# du -h test.txt 4.0K test.txt [[email protected] ~]# truncate -s 0 test.txt -s参数用来设定文件的大小,清空文件,就设定为0; [[email protected] ~]# du -h test.txt 0 test.txt
原创文章,作者:ItWorker,如若转载,请注明出处:https://blog.ytso.com/3030.html