1 .TH alloc 3

     2 .SH NAME

     3 alloc \- allocate memory

     4 .SH SYNTAX

     5 .B #include <alloc.h>

     6 

     7 char *\fBalloc\fP(\fInew\fR);

     8 

     9 void \fBalloc_free\fP(\fIx\fR);

    10 

    11 void \fBalloc_re\fP(&\fIx\fR,\fIold\fR,\fInew\fR);

    12 

    13 char *\fIx\fR;

    14 .br

    15 unsigned int \fIold\fR;

    16 .br

    17 unsigned int \fInew\fR;

    18 .SH DESCRIPTION

    19 .B alloc

    20 allocates enough space from the heap for

    21 .I new

    22 bytes of data,

    23 adequately aligned for any data type.

    24 .I new

    25 may be 0.

    26 .B alloc

    27 returns a pointer to the space.

    28 If space is not available,

    29 .B alloc

    30 returns 0,

    31 setting

    32 .B errno

    33 appropriately.

    34 

    35 .B alloc_free

    36 returns space to the heap.

    37 

    38 .B alloc_re

    39 expands the space allocated to

    40 .I x

    41 from

    42 .I old

    43 bytes to

    44 .I new

    45 bytes.

    46 It allocates new space,

    47 copies

    48 .I old

    49 bytes from the old space to the new space,

    50 returns the old space to the heap,

    51 and changes

    52 .I x

    53 to point to the new space.

    54 It then returns 1.

    55 If space is not available,

    56 .B alloc_re

    57 returns 0,

    58 leaving the old space alone.

    59 .SH "SEE ALSO"

    60 sbrk(2),

    61 malloc(3),

    62 error(3)