whereis is a Unix command used to locate some special files of a Unix command like the binary, source and manual page files. Unix
type is usually preferred to locate a binary file, because it is POSIX and it can identify shell aliases.
Here is an example usage from the man page:
# Find all files in /usr/bin which are not documented in /usr/man/man1 with source in /usr/src: % cd /usr/bin % whereis -u -M /usr/man/man1 -S /usr/src -f *
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