overgrown/docs/intcmp.1

.\" Copyright (c) 2023–2024 DTB <trinity@trinity.moe>
.\" Copyright (c) 2023–2024 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 INTCMP 1
.SH NAME
intcmp \(en compare integers
.\"
.SH SYNOPSIS

intcmp
.RB ( -egl )
.RB [ integer ]
.RB [ integer... ]
.SH DESCRIPTION
Compare integers to each other.
.\"
.SH OPTIONS

.IP \fB-e\fP
Permits given integers to be equal to each other.
.IP \fB-g\fP
Permits a given integer to be greater than the following integer.
.IP \fB-l\fP
Permits a given integer to be less than the following integer.
.\"
.SH EXAMPLES

It may help to think of the -e, -g, and -l options as equivalent to the
infix algebraic \(lq=\(rq, \(lq>\(rq, and \(lq<\(rq operators respectively, with
each option putting its symbol between every given integer. The following
example is equivalent to evaluating \(lq1 < 2 < 3\(rq:

.RS
.R intcmp -l 1 2 3
.RE
.\"
.SH DIAGNOSTICS

The program will exit with a status code of 0 for a valid expression and with a
code of 1 for an invalid expression.

In the event of an error, a debug message will be printed and the program will
exit with the appropriate
.BR sysexits.h (3)
error code.
.\"
.SH BUGS

-egl, \(lqequal to or less than or greater than\(rq, exits 0 no matter what for
valid program usage and may be abused to function as an integer validator. Use
.BR str (1)
instead.
.\"
.SH CAVEATS

There are multiple ways to express compound comparisons; \(lqless than or equal
to\(rq can be -le or -el, for example.

The inequality comparison is -gl or -lg for \(lqless than or greater than\(rq;
this is elegant but unintuitive.
.\"
.SH RATIONALE

The traditional tool for integer comparisons in POSIX and other Unix shells has
been
.BR test (1).
This tool also handles string comparisons and file scrutiny. These parts of its
functionality have been broken out into multiple utilities.

This program\(cqs functionality may be performed on a POSIX-compliant system
with
.BR test (1p).
.\"
.SH AUTHOR

Written by DTB
.MT trinity@trinity.moe
.ME .
.\"
.SH COPYRIGHT
.\"
Copyright \(co 2023 DTB. License AGPLv3+: GNU AGPL version 3 or later
<https://gnu.org/licenses/gpl.html>.
.\"
.SH SEE ALSO
.BR scrut (1),
.BR strcmp (1),
.BR str (1),
.BR test (1p)