+++ /dev/null
-.\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.TH STRVERSCMP 3 2001-12-19 "GNU" "Linux Programmer's Manual"
-.SH NAME
-strverscmp \- compare two version strings
-.SH SYNOPSIS
-.nf
-.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */"
-.br
-.B #include <string.h>
-.sp
-.BI "int strverscmp(const char *" s1 ", const char *" s2 );
-.fi
-.SH DESCRIPTION
-Often one has files
-.IR jan1 ", " jan2 ", ..., " jan9 ", " jan10 ", ..."
-and it feels wrong when
-.BR ls (1)
-orders them
-.IR jan1 ", " jan10 ", ..., " jan2 ", ..., " jan9 .
-.\" classical solution: "rename jan jan0 jan?"
-In order to rectify this, GNU introduced the
-.I \-v
-option to
-.BR ls (1),
-which is implemented using
-.BR versionsort (3),
-which again uses
-.BR strverscmp ().
-
-Thus, the task of
-.BR strverscmp ()
-is to compare two strings and find the "right" order, while
-.BR strcmp (3)
-finds only the lexicographic order.
-This function does not use
-the locale category
-.BR LC_COLLATE ,
-so is meant mostly for situations
-where the strings are expected to be in ASCII.
-
-What this function does is the following.
-If both strings are equal, return 0.
-Otherwise, find the position
-between two bytes with the property that before it both strings are equal,
-while directly after it there is a difference.
-Find the largest consecutive digit strings containing (or starting at,
-or ending at) this position.
-If one or both of these is empty,
-then return what
-.BR strcmp (3)
-would have returned (numerical ordering of byte values).
-Otherwise, compare both digit strings numerically, where digit strings with
-one or more leading zeros are interpreted as if they have a decimal point
-in front (so that in particular digit strings with more leading zeros
-come before digit strings with fewer leading zeros).
-Thus, the ordering is
-.IR 000 ", " 00 ", " 01 ", " 010 ", " 09 ", " 0 ", " 1 ", " 9 ", " 10 .
-.SH RETURN VALUE
-The
-.BR strverscmp ()
-function returns an integer
-less than, equal to, or greater than zero if
-.I s1
-is found, respectively, to be earlier than, equal to,
-or later than
-.IR s2 .
-.SH CONFORMING TO
-This function is a GNU extension.
-.SH SEE ALSO
-.BR rename (1),
-.BR strcasecmp (3),
-.BR strcmp (3),
-.BR strcoll (3)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
OSDN Git Service
