Linux file command

Linux Command Reference

The Linux file command is used to identify file types.

With the file command, we can identify the type of the file.

Syntax

file [-bcLvz][-f <名称文件>][-m <魔法数字文件>...][文件或目录...]

Options：

• -b When listing identification results, do not display the file name.
• -c Displays the execution process in detail, making it easier to debug or analyze the program execution.
• -f<name file> Specifies a name file. When its content contains one or more file names, let file identify these files in sequence; the format is one file name per line.
• -L Directly displays the type of the file pointed to by a symbolic link.
• -m<magic number file> Specifies the magic number file.
• -v Displays version information.
• -z Attempts to interpret the contents of compressed files.
• [File or directory...] A list of files whose types are to be determined. Separate multiple files with spaces. Shell wildcards can be used to match multiple files.

Examples

Display file type:

[root@localhost ~]# file install.log
install.log: UTF-8 Unicode text

[root@localhost ~]# file -b install.log      <== 不显示文件名称
UTF-8 Unicode text

[root@localhost ~]# file -i install.log      <== 显示MIME类别。
install.log: text/plain; charset=utf-8

[root@localhost ~]# file -b -i install.log
text/plain; charset=utf-8

Display the file type of a symbolic link

[root@localhost ~]# ls -l /var/mail
lrwxrwxrwx 1 root root 10 08-13 00:11 /var/mail -> spool/mail

[root@localhost ~]# file /var/mail
/var/mail: symbolic link to `spool/mail'

[root@localhost ~]# file -L /var/mail
/var/mail: directory

[root@localhost ~]# file /var/spool/mail
/var/spool/mail: directory

[root@localhost ~]# file -L /var/spool/mail
/var/spool/mail: directory

Linux Command Reference