The use and difference between the install and cp commands in linux

preface

install and cp are similar in that you can copy files/directories to a specified location. However, install allows you to control the properties of the target file. install is commonly used in the makefile of a program (and also in spec of RPM) to copy the program to the target (installation) directory.

The main usage of install is as follows:

install [OPTION]… SOURCE… DIRECTORY


At this point, DIRECTORY must exist or be treated as a new file

install [OPTION]… -t DIRECTORY SOURCE…

install [OPTION]… -d DIRECTORY…

If the directory does not exist, create it

-b: backup every existing destination file;

-D: create all directories before the destination, then copy the source to the destination

-g: set the group to which you belong;

-m: set your own permissions instead of the default rwxr-xr-x

-o: set the owner yourself

-p: takes the modification time of the source file as the file attribute of the corresponding destination

Such as:

@install -d /usr/bin
@install -p -D -m 0755 targets /usr/bin
 The equivalent of 
@mkdir -p /usr/bin
@cp targets /usr/bin
@chmod 755 /usr/bin/targets
@touch /usr/bin/tagets <----  Update the file timestamp 
<----@ The prefix means that the output is not in the console. 

install and cp accomplish the same task by copying files. The differences between them are as follows:

1. The most important point is that if the target file exists, cp will first empty the file and then write a new file into it, while install will first delete the original file and then write to the new file. This is because writing to a file in use can cause problems, such as failing to write to an executing file, or writing a new file to a file handle that is already being written to. This can be avoided by using install to delete and then write (which generates a new file handle).

2. The install command handles file permissions properly. For example, install-c will set the permissions of the target file to rwxr-xr-x;

3. The install command prints out more and more appropriate debug information and handles SElinux context issues automatically.

conclusion

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