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Length: 700 (0x2bc)
Types: TextFile
Notes: UNIX file
Names: »sbrk.c«
└─⟦f27320a65⟧ Bits:30001972 Commodore 900 hard disk image with partial source code
└─⟦f4b8d8c84⟧ UNIX V7 Filesystem
└─ ⟦this⟧ »libc/sys/sbrk.c«
/*
* Sbrk - grow memory in data segment by
* a specified increment.
* Special version that does Commodore Large model Z8001
*/
#include <stdio.h>
#include <types.h>
extern int errno;
extern vaddr_t __end;
char *
sbrk(incr)
unsigned int incr;
{
extern char *brk();
register vaddr_t send,
rend;
#if 1 /* On the z8001 (at least) reduce the waste */
rend = __end;
#else
rend = brk(NULL);
#endif
if (incr == 0)
return (rend);
#if Z8001
if (((unsigned)rend+incr) < (unsigned)rend)
rend = rend - (unsigned)rend +0x01000000L;
send = rend + incr;
#else
send = rend + incr;
if (send < rend)
return (NULL);
#endif
errno = 0;
brk(send);
if (errno)
return (NULL);
return (rend);
}