KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> writes: > On Mon, 18 Jan 2010 10:38:27 +0900 > OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> wrote: > >> KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> writes: >> >> >> So, lseek() returns (uses) it? >> > >> > lseek can return negative value, as far as I know. >> >> Umm..., how do you know the difference of -EOVERFLOW and fpos == -75? >> > > Ah, sorry. I read wrong. > > For /dev/mem, it uses its own lseek function which allows negative f_pos > value. Other usual file system doesn't allow negative f_pos. > > It's ok not to return -EOVEFLOW for /dev/mem because there is no file end. No, no. I think it has the problem. E.g. /dev/mem returns -75 as fpos, so, lseek(2) returns -75 to userland. Then the userland (e.g. glibc) convert it as error. I.e. finally, errno == -75, and lseek(3) returns -1, right? Thanks. -- OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
