mkdir
mkdir命令：创建指定的目录，要求创建的用户在当前目录具有写权限，并且指定的目录名不能是当前目录中已有的目录
mkdir：make directory的缩写
命令格式：mkier 【选项】 目录
Common parameters
| parameter | description |
|---|---|
| -m --mode = mode | Set permissions <mode> |
| -p --parents | You can make a path name. If some of the directory path does not exist yet, after adding this option, the system will automatically build a good directory which does not yet exist, that one can create multiple directories |
| -v --verbose | Each time you create a new directory will display information |
Common examples
Example a: a plurality of recursively create directory, create file three
mkdir -pa / b / c
Example Two: Create directory permissions 777
mkdir -m 777 a
Example Two: Create a directory display information
mkdir -vp a / b
rm command
rm：删除一个目录中的一个或多个文件或目录，它也可以将某个目录及其下的所有文件及子目录均删除。对于链接文件，只会删除链接，原文件均保持不变
rm:remove的缩写
命令格式：rm 【选项】 文件或目录
Common parameters:
| parameter | description |
|---|---|
| -f --force | Ignore nonexistent files, never prompt |
| -i --interactive | Interactive deleted |
| -r --recursive | Rm indicate all the parameters listed in directories and subdirectories are recursively deleted |
| -v --verbose | Showing in detail step |
Common examples
delete a file: rm test
forcibly remove the file, the system will not prompt: rm -f test
mv command
mv:用来移动文件或更改文件名
mv: move的缩写
命令格式： mv 【选项】 源文件或目录 目标文件或目录
Common parameters
| parameter | description |
|---|---|
| -b --back | For overwrite the file, the front cover to back up |
| -f --force | If the target file already exists, do not ask directly covered |
| -i --interactive | If the target file already exists, it will ask whether to overwrite |
| -u --update | If the target file already exists, and the relatively new source file is not updated |
| -t --target | This option is applicable to a mobile multiple source files to a directory, in which case the former target directory, the source file after |
Common examples
Example a: a file rename b: mv ab
Example Two: move the file to a directory test: a test Music Videos
Example Three: a.txt move to the file directory test1, if the file exists, covers the front asking to overwrite: mv -i a.txt test1
cp command
cp命令是用来复制文件或者目录
cp:copy的缩写
命令格式：cp 【选项】 源文件 目录
Common parameters
| parameter | description |
|---|---|
| -t --target-dirctory | Specified target directory |
| -i --interactive | Ask before overwrite (the failure of the previous -n option) |
| -n --no-clobbe | Do not overwrite an existing file (the front of the -i option failure) |
| -s --symbolic-link | Create a symbolic link to the source file, rather than copying files |
| -f --force | Forced copy a file or directory, regardless of the destination file already exists |
| -u --update | After using this parameter, only the source file modification time than the destination file |
Example One: Create a symbolic link to the file b a: cp -sab
Example Two: Copy all files in the directory to test1 test2 directory, Ask before overwrite: cp -i test1 / * test2
Example Three: The next test1 directory copy the file to the recently updated test2 directory, ask before overwrite: cp -ui test1 / * test2
The cat command
cat：将文件或标准输出到标准输出，用来显示文件内容，或将几个连接起来显示
cat :concatenate的缩写
命令格式
cat 【选项】 【文件】
Common parameters
| parameter | description |
|---|---|
| -n --number | All numbers output numbered starting from a number of rows of all outputs |
| -s --squeeze-blank | There are more than two consecutive lines blank, blank lines on the substitution line |
Example 1: the contents of the file with a line number input a.txt b.txt this file:
CAT a.txt -n> b.txt
Example 2: the contents with a line number a.txt b.txt input to the file, multiple blank lines into one line of output:
CAT -NS a.txt> b.txt
Example three: the reverse display file contents a.txt
tac a.txt
This in turn write tac is cat
nl command
To view the contents of the file
format: nl [file]
