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NAME |LIBRARY |SYNOPSIS |DESCRIPTION |RETURN VALUE |ATTRIBUTES |STANDARDS |EXAMPLES |SEE ALSO |COLOPHON | |
strverscmp(3) Library Functions Manualstrverscmp(3)strverscmp - compare two version strings
Standard C library (libc,-lc)
#define _GNU_SOURCE/* See feature_test_macros(7) */#include <string.h>int strverscmp(const char *s1, const char *s2);
For a dataset likejan1,jan2, ...,jan9,jan10, ... sorting it lexicographically yieldsjan1,jan10, ...,jan2, ...,jan9. The task ofstrverscmp() is to compare two strings yielding the former order, whilestrcmp(3) finds only the lexicographic order. This function does not use the locale categoryLC_COLLATE, so is meant mostly for situations where the strings are expected to be in ASCII. This is different from the ordering produced bysort(1)-V. 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 whatstrcmp(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 is000,00,01,010,09,0,1,9,10.
Thestrverscmp() function returns an integer less than, equal to, or greater than zero ifs1 is found, respectively, to be earlier than, equal to, or later thans2.
For an explanation of the terms used in this section, seeattributes(7). ┌──────────────────────────────────────┬───────────────┬─────────┐ │Interface│Attribute│Value│ ├──────────────────────────────────────┼───────────────┼─────────┤ │strverscmp() │ Thread safety │ MT-Safe │ └──────────────────────────────────────┴───────────────┴─────────┘
GNU.
The program below can be used to demonstrate the behavior ofstrverscmp(). It usesstrverscmp() to compare the two strings given as its command-line arguments. An example of its use is the following: $./a.out jan1 jan10; jan1 < jan10Program source #define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> #include <string.h> int main(int argc, char *argv[]) { int res; if (argc != 3) { fprintf(stderr, "Usage: %s <string1> <string2>\n", argv[0]); exit(EXIT_FAILURE); } res = strverscmp(argv[1], argv[2]); printf("%s %s %s\n", argv[1], (res < 0) ? "<" : (res == 0) ? "==" : ">", argv[2]); exit(EXIT_SUCCESS); }rename(1),strcasecmp(3),strcmp(3),strcoll(3)
This page is part of theman-pages (Linux kernel and C library user-space interface documentation) project. Information about the project can be found at ⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report for this manual page, see ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩. This page was obtained from the tarball man-pages-6.15.tar.gz fetched from ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on 2025-08-11. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up- to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.orgLinux man-pages 6.15 2025-05-17strverscmp(3)Pages that refer to this page:scandir(3), strcmp(3), mount(8), swapon(8)
HTML rendering created 2025-09-06 byMichael Kerrisk, author ofThe Linux Programming Interface. For details of in-depthLinux/UNIX system programming training courses that I teach, lookhere. Hosting byjambit GmbH. | |