You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
52 lines
1.8 KiB
Groff
52 lines
1.8 KiB
Groff
.TH array_allocate 3
|
|
.SH NAME
|
|
array_allocate \- make sure array has at least n elements allocated
|
|
.SH SYNTAX
|
|
.B #include <array.h>
|
|
|
|
void* \fBarray_allocate\fP(array* \fIx\fR, uint64 \fImembersize\fR, int64 \fIpos\fR);
|
|
|
|
array \fIx\fR;
|
|
int64 \fIpos\fR;
|
|
\fIt\fR* p = array_allocate(&\fIx\fR,sizeof(\fIt\fR),\fIpos\fR);
|
|
|
|
.SH DESCRIPTION
|
|
array_allocate makes sure that enough bytes are allocated in \fIx\fR for
|
|
at least \fIpos\fR+1 objects of type \fIt\fR. (The size of \fIt\fR must
|
|
be positive; otherwise the effects are undefined.) If not enough bytes
|
|
are allocated (or \fIx\fR is unallocated), array_allocate allocates more
|
|
bytes, moving the dynamically allocated region if necessary.
|
|
array_allocate often allocates somewhat more bytes than necessary, to
|
|
save time later.
|
|
|
|
array_allocate then makes sure that the number of bytes initialized
|
|
covers at least those \fIpos\fR+1 objects. If not enough bytes are
|
|
initialized, array_allocate initializes more bytes (setting them to 0),
|
|
up to exactly the end of the \fIpos\fR+1st object.
|
|
|
|
array_allocate then returns a pointer to the \fIpos\fR+1st object; i.e.,
|
|
object number \fIpos\fR, with objects numbered starting at 0. This
|
|
pointer can be used to change or inspect the object. The pointer can
|
|
continue to be used through subsequent calls to array_get, array_start,
|
|
array_length, and array_bytes, but it must not be used after any other
|
|
operations on this array.
|
|
|
|
If something goes wrong, array_allocate returns 0, setting \fBerrno\fR
|
|
appropriately, without touching \fIx\fR. In particular, array_allocate
|
|
returns 0 if
|
|
|
|
.sp 1
|
|
.IP \(bu
|
|
\fIx\fR has failed, or
|
|
.IP \(bu
|
|
\fIpos\fR is negative, or
|
|
.IP \(bu
|
|
not enough memory is available.
|
|
.PP
|
|
|
|
array_allocate does \fInot\fR change \fIx\fR to have failed; if you want
|
|
to do that, use array_fail.
|
|
|
|
.SH "SEE ALSO"
|
|
array_get(3), array_start(3), array_fail(3)
|