whereis

The `whereis` command is a Unix and Linux utility used to locate the binary, source, and manual page files for a given command. It searches a predefined set of standard locations on the system for these files.

When you run `whereis command_name`, the output typically consists of three parts separated by colons. The first part is the name of the command. The second part lists the paths to the executable binary files associated with that command. The third part lists the paths to the source code files, if available. The fourth part lists the paths to the manual pages (man pages) for the command.

For example, running `whereis ls` might produce output like `ls: /bin/ls /usr/share/man/man1/ls.1.gz`. This indicates that the `ls` executable is located at `/bin/ls` and its manual page is at `/usr/share/man/man1/ls.1.gz`. The `whereis` command is useful for system administrators and users who need to quickly find the locations of system files or understand where different components of a program are installed. It's important to note that `whereis` has a limited search scope and does not search through the user's PATH environment variable for executables, unlike the `which` command.

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