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Diffstat (limited to 'man3/malloc.3')
| -rw-r--r-- | man3/malloc.3 | 111 |
1 files changed, 80 insertions, 31 deletions
diff --git a/man3/malloc.3 b/man3/malloc.3 index 71b776f86..eee0b3069 100644 --- a/man3/malloc.3 +++ b/man3/malloc.3 @@ -1,6 +1,6 @@ '\" t .\" Copyright (c) 1993 by Thomas Koenig (ig25@rz.uni-karlsruhe.de) -.\" and Copyright i2007, 2012, 2018, Michael Kerrisk <mtk.manpages@gmail.com> +.\" and Copyright 2007, 2012, 2018, Michael Kerrisk <mtk.manpages@gmail.com> .\" .\" SPDX-License-Identifier: Linux-man-pages-copyleft .\" @@ -12,7 +12,7 @@ .\" FIXME . Review http://austingroupbugs.net/view.php?id=374 .\" to see what changes are required on this page. .\" -.TH malloc 3 2023-02-05 "Linux man-pages 6.03" +.TH malloc 3 2023-07-20 "Linux man-pages 6.05.01" .SH NAME malloc, free, calloc, realloc, reallocarray \- allocate and free dynamic memory .SH LIBRARY @@ -22,11 +22,11 @@ Standard C library .nf .B #include <stdlib.h> .PP -.BI "void *malloc(size_t " "size" ); -.BI "void free(void " "*ptr" ); -.BI "void *calloc(size_t " "nmemb" ", size_t " "size" ); -.BI "void *realloc(void " "*ptr" ", size_t " "size" ); -.BI "void *reallocarray(void " "*ptr" ", size_t " nmemb ", size_t " "size" ); +.BI "void *malloc(size_t " size ); +.BI "void free(void *_Nullable " ptr ); +.BI "void *calloc(size_t " nmemb ", size_t " size ); +.BI "void *realloc(void *_Nullable " ptr ", size_t " size ); +.BI "void *reallocarray(void *_Nullable " ptr ", size_t " nmemb ", size_t " size ); .fi .PP .RS -4 @@ -226,48 +226,65 @@ or .B RLIMIT_DATA limit described in .BR getrlimit (2). -.SH VERSIONS -.BR reallocarray () -was added in glibc 2.26. -.PP -.BR malloc () -and related functions rejected sizes greater than -.B PTRDIFF_MAX -starting in glibc 2.30. -.PP -.BR free () -preserved -.I errno -starting in glibc 2.33. +Another reason could be that +the number of mappings created by the caller process +exceeded the limit specified by +.IR /proc/sys/vm/max_map_count . .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{ +.na +.nh .BR malloc (), .BR free (), .BR calloc (), .BR realloc () T} Thread safety MT-Safe .TE -.hy -.ad .sp 1 .SH STANDARDS -.BR malloc (), -.BR free (), -.BR calloc (), -.BR realloc (): -POSIX.1-2001, POSIX.1-2008, C99. -.PP +.TP +.BR malloc () +.TQ +.BR free () +.TQ +.BR calloc () +.TQ +.BR realloc () +C11, POSIX.1-2008. +.TP .BR reallocarray () -is a nonstandard extension that first appeared in OpenBSD 5.6 and FreeBSD 11.0. +None. +.SH HISTORY +.TP +.BR malloc () +.TQ +.BR free () +.TQ +.BR calloc () +.TQ +.BR realloc () +POSIX.1-2001, C89. +.TP +.BR reallocarray () +glibc 2.26. +OpenBSD 5.6, FreeBSD 11.0. +.PP +.BR malloc () +and related functions rejected sizes greater than +.B PTRDIFF_MAX +starting in glibc 2.30. +.PP +.BR free () +preserved +.I errno +starting in glibc 2.33. .SH NOTES By default, Linux follows an optimistic memory allocation strategy. This means that when @@ -381,6 +398,38 @@ as POSIX and the C standard do not allow replacement of .BR calloc (), and .BR realloc (). +.SH EXAMPLES +.EX +#include <err.h> +#include <stddef.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +\& +#define MALLOCARRAY(n, type) ((type *) my_mallocarray(n, sizeof(type))) +#define MALLOC(type) MALLOCARRAY(1, type) +\& +static inline void *my_mallocarray(size_t nmemb, size_t size); +\& +int +main(void) +{ + char *p; +\& + p = MALLOCARRAY(32, char); + if (p == NULL) + err(EXIT_FAILURE, "malloc"); +\& + strlcpy(p, "foo", 32); + puts(p); +} +\& +static inline void * +my_mallocarray(size_t nmemb, size_t size) +{ + return reallocarray(NULL, nmemb, size); +} +.EE .SH SEE ALSO .\" http://g.oswego.edu/dl/html/malloc.html .\" A Memory Allocator - by Doug Lea |