usrlocalsharemanman3

usrlocalsharemanman3 is a flattened reference to the filesystem location /usr/local/share/man/man3, the directory in Unix-like systems where locally installed manual pages for section 3 are stored. Section 3 of the man page hierarchy covers library functions and related routines, primarily those implemented by programming libraries rather than user commands or system calls.

The /usr/local/share/man/man3 directory is used to host manual pages for software that has been installed outside the distribution’s default package manager, such as programs built from source or third‑party libraries. Files here are typically named for the function or API they document and are stored in either plain text or gzip-compressed form, with a .3 or .3.gz suffix to indicate section 3 content.

To read a page from this location, the system’s man utility must be able to locate it. This can be done by ensuring the directory is included in the MANPATH environment variable (for example, using the -M option with man) or by placing the page in the system’s default man path. The command mandb can be used to update the manual database so new or relocated pages are discoverable.

Common practice is that base system pages reside in /usr/share/man/man3, while locally installed pages go under /usr/local/share/man/man3. For example, a locally installed library function named foo_open might be documented as foo_open.3.gz within this directory. Maintaining this separation helps distinguish vendor-supplied documentation from locally installed or custom software.