Question

I need to write a repeating pattern to memory (e.g. 0x11223344), so that the whole memory looks like (in hex):

1122334411223344112233441122334411223344112233441122334411223344...

I can’t figure out how to do it with memset() because it takes only a single byte, not 4 bytes.

Any ideas?

Answer 1

An efficient way would be to cast the pointer to a pointer of the needed size in bytes (e.g. uint32_t for 4 bytes) and fill with integers. It’s a little ugly though.

char buf[256] = { 0, };
uint32_t * p = (uint32_t *) buf, i;

for (i = 0; i < sizeof(buf) / sizeof(* p); i++) {
    p[i] = 0x11223344;
}

Not tested!