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+.\" Copyright (c) 2024 Emma Tebibyte <emma@tebibyte.media>
+.\"
+.\" This work is licensed under CC BY-SA 4.0. To see a copy of this license,
+.\" visit <http://creativecommons.org/licenses/by-sa/4.0/>.
+
+.TH rpn 1
+
+.SH NAME
+
+hru \(en human readable units
+
+.SH SYNOPSIS
+
+hru
+
+.SH DESCRIPTION
+
+Hru takes any whole number in the standard input and, to the standard output,
+prints the equivalent number in the most human-readable unit defined by the 
+International System of Units.
+
+.SH DIAGNOSTICS
+
+If encountering non-integer characters in the standard input, hru will exit with
+the appropriate error code as defined by sysexits.h(3) and print an error
+message.
+
+.SH RATIONALE
+
+The GNU project’s ls(1) implementation contains a human-readable option (-h)
+that, when specified, makes the tool print size information in a format more
+immediately readable. This functionality is not useful only in the context of
+ls(1) so the decision was made to split it into a new tool. The original
+functionality in GNU’s ls(1) can be emulated with fop(1) combined with this
+program.
+
+.SH STANDARDS
+
+Hru follows the standard Internation System of Units prefixes as specified by
+the General Conference on Weights and Measures (CGPM).
+
+.SH AUTHOR
+
+Written by Emma Tebibyte <emma@tebibyte.media>.
+
+.SH COPYRIGHT
+
+Copyright (c) 2024 Emma Tebibyte. License AGPLv3+: GNU AGPL version 3 or later
+<https://gnu.org/licenses/agpl.html>.
+
+.SH SEE ALSO
+
+GNU ls(1), CGPM Resolution 3 (2022)