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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 19:43:11 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-15 19:43:11 +0000 |
commit | fc22b3d6507c6745911b9dfcc68f1e665ae13dbc (patch) | |
tree | ce1e3bce06471410239a6f41282e328770aa404a /upstream/archlinux/man3p/realloc.3p | |
parent | Initial commit. (diff) | |
download | manpages-l10n-fc22b3d6507c6745911b9dfcc68f1e665ae13dbc.tar.xz manpages-l10n-fc22b3d6507c6745911b9dfcc68f1e665ae13dbc.zip |
Adding upstream version 4.22.0.upstream/4.22.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'upstream/archlinux/man3p/realloc.3p')
-rw-r--r-- | upstream/archlinux/man3p/realloc.3p | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/upstream/archlinux/man3p/realloc.3p b/upstream/archlinux/man3p/realloc.3p new file mode 100644 index 00000000..62ff6c54 --- /dev/null +++ b/upstream/archlinux/man3p/realloc.3p @@ -0,0 +1,179 @@ +'\" et +.TH REALLOC "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +realloc +\(em memory reallocator +.SH SYNOPSIS +.LP +.nf +#include <stdlib.h> +.P +void *realloc(void *\fIptr\fP, size_t \fIsize\fP); +.fi +.SH DESCRIPTION +The functionality described on this reference page is aligned with the +ISO\ C standard. Any conflict between the requirements described here and the +ISO\ C standard is unintentional. This volume of POSIX.1\(hy2017 defers to the ISO\ C standard. +.P +The +\fIrealloc\fR() +function shall deallocate the old object pointed to by +.IR ptr +and return a pointer to a new object that has the size specified by +.IR size . +The contents of the new object shall be the same as that of the old +object prior to deallocation, up to the lesser of the new and old +sizes. Any bytes in the new object beyond the size of the old object +have indeterminate values. If the size of the space requested is zero, +the behavior shall be implementation-defined: either a null pointer is +returned, or the behavior shall be as if the size were some non-zero +value, except that the behavior is undefined if the returned pointer +is used to access an object. If the space cannot be allocated, +the object shall remain unchanged. +.P +If +.IR ptr +is a null pointer, +\fIrealloc\fR() +shall be equivalent to +\fImalloc\fR() +for the specified size. +.P +If +.IR ptr +does not match a pointer returned earlier by +\fIcalloc\fR(), +\fImalloc\fR(), +or +\fIrealloc\fR() +or if the space has previously been deallocated by a call to +\fIfree\fR() +or +\fIrealloc\fR(), +the behavior is undefined. +.P +The order and contiguity of storage allocated by successive calls to +\fIrealloc\fR() +is unspecified. The pointer returned if the allocation succeeds shall +be suitably aligned so that it may be assigned to a pointer to any type +of object and then used to access such an object in the space allocated +(until the space is explicitly freed or reallocated). Each such +allocation shall yield a pointer to an object disjoint from any other +object. The pointer returned shall point to the start (lowest byte +address) of the allocated space. If the space cannot be allocated, a +null pointer shall be returned. +.SH "RETURN VALUE" +Upon successful completion, +\fIrealloc\fR() +shall return a pointer to the (possibly moved) allocated space. If +.IR size +is 0, either: +.IP " *" 4 +A null pointer shall be returned +and, if +.IR ptr +is not a null pointer, +.IR errno +shall be set to an implementation-defined value. +.IP " *" 4 +A pointer to the allocated space shall be returned, and the +memory object pointed to by +.IR ptr +shall be freed. The application shall ensure that the pointer is not +used to access an object. +.P +If there is not enough available memory, +\fIrealloc\fR() +shall return a null pointer +and set +.IR errno +to +.BR [ENOMEM] . +If +\fIrealloc\fR() +returns a null pointer +and +.IR errno +has been set to +.BR [ENOMEM] , +the memory referenced by +.IR ptr +shall not be changed. +.SH ERRORS +The +\fIrealloc\fR() +function shall fail if: +.TP +.BR ENOMEM +Insufficient memory is available. +.LP +.IR "The following sections are informative." +.SH EXAMPLES +None. +.SH "APPLICATION USAGE" +The description of +\fIrealloc\fR() +has been modified from previous versions of this standard to align +with the ISO/IEC\ 9899:\|1999 standard. Previous versions explicitly permitted a call to +.IR realloc \c +(\fIp\fI, 0) to free the space pointed to by +.IR p +and return a null pointer. While this behavior could be interpreted as +permitted by this version of the standard, the C language committee have +indicated that this interpretation is incorrect. Applications should +assume that if +\fIrealloc\fR() +returns a null pointer, the space pointed to by +.IR p +has not been freed. Since this could lead to double-frees, implementations +should also set +.IR errno +if a null pointer actually indicates a failure, and applications should +only free the space if +.IR errno +was changed. +.SH RATIONALE +None. +.SH "FUTURE DIRECTIONS" +This standard defers to the ISO\ C standard. While that standard currently has +language that might permit +.IR realloc \c +(\fIp\fI, 0), where +.IR p +is not a null pointer, to free +.IR p +while still returning a null pointer, the committee responsible for that +standard is considering clarifying the language to explicitly prohibit +that alternative. +.SH "SEE ALSO" +.IR "\fIcalloc\fR\^(\|)", +.IR "\fIfree\fR\^(\|)", +.IR "\fImalloc\fR\^(\|)" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "\fB<stdlib.h>\fP" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +In the event of any discrepancy between this version and the original IEEE and +The Open Group Standard, the original IEEE and The Open Group Standard +is the referee document. The original Standard can be obtained online at +http://www.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |