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diff --git a/man3/qsort.3 b/man3/qsort.3 deleted file mode 100644 index 955f8cb43..000000000 --- a/man3/qsort.3 +++ /dev/null @@ -1,160 +0,0 @@ -'\" t -.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code -.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) -.\" 386BSD man pages -.\" -.\" Modified 1993-03-29, David Metcalfe -.\" Modified 1993-07-24, Rik Faith (faith@cs.unc.edu) -.\" 2006-01-15, mtk, Added example program. -.\" Modified 2012-03-08, Mark R. Bannister <cambridge@users.sourceforge.net> -.\" and Ben Bacarisse <software@bsb.me.uk> -.\" Document qsort_r() -.\" -.TH qsort 3 (date) "Linux man-pages (unreleased)" -.SH NAME -qsort, qsort_r \- sort an array -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <stdlib.h> -.PP -.BI "void qsort(void " base [. size " * ." nmemb "], size_t " nmemb ", \ -size_t " size , -.BI " int (*" compar ")(const void [." size "], \ -const void [." size ])); -.BI "void qsort_r(void " base [. size " * ." nmemb "], size_t " nmemb ", \ -size_t " size , -.BI " int (*" compar ")(const void [." size "], \ -const void [." size "], void *)," -.BI " void *" arg ");" -.fi -.PP -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.PP -.BR qsort_r (): -.nf - _GNU_SOURCE -.fi -.SH DESCRIPTION -The -.BR qsort () -function sorts an array with \fInmemb\fP elements of -size \fIsize\fP. -The \fIbase\fP argument points to the start of the -array. -.PP -The contents of the array are sorted in ascending order according to a -comparison function pointed to by \fIcompar\fP, which is called with two -arguments that point to the objects being compared. -.PP -The comparison function must return an integer less than, equal to, or -greater than zero if the first argument is considered to be respectively -less than, equal to, or greater than the second. -If two members compare as equal, -their order in the sorted array is undefined. -.PP -The -.BR qsort_r () -function is identical to -.BR qsort () -except that the comparison function -.I compar -takes a third argument. -A pointer is passed to the comparison function via -.IR arg . -In this way, the comparison function does not need to use global variables to -pass through arbitrary arguments, and is therefore reentrant and safe to -use in threads. -.SH RETURN VALUE -The -.BR qsort () -and -.BR qsort_r () -functions return no value. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.ad l -.nh -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.BR qsort (), -.BR qsort_r () -T} Thread safety MT-Safe -.TE -.hy -.ad -.sp 1 -.SH STANDARDS -.TP -.BR qsort () -C11, POSIX.1-2008. -.SH HISTORY -.TP -.BR qsort () -POSIX.1-2001, C89, SVr4, 4.3BSD. -.TP -.BR qsort_r () -glibc 2.8. -.SH NOTES -To compare C strings, the comparison function can call -.BR strcmp (3), -as shown in the example below. -.SH EXAMPLES -For one example of use, see the example under -.BR bsearch (3). -.PP -Another example is the following program, -which sorts the strings given in its command-line arguments: -.PP -.\" SRC BEGIN (qsort.c) -.EX -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -\& -static int -cmpstringp(const void *p1, const void *p2) -{ - /* The actual arguments to this function are "pointers to - pointers to char", but strcmp(3) arguments are "pointers - to char", hence the following cast plus dereference. */ -\& - return strcmp(*(const char **) p1, *(const char **) p2); -} -\& -int -main(int argc, char *argv[]) -{ - if (argc < 2) { - fprintf(stderr, "Usage: %s <string>...\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - qsort(&argv[1], argc \- 1, sizeof(char *), cmpstringp); -\& - for (size_t j = 1; j < argc; j++) - puts(argv[j]); - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.BR sort (1), -.BR alphasort (3), -.BR strcmp (3), -.BR versionsort (3) |