On Sun, 2 Sep 2012 17:05:20 +0200 Cedric Blancher wrote: > On 2 September 2012 16:37, Glenn Fowler <g...@research.att.com> wrote: > > > > On Sun, 2 Sep 2012 12:43:58 +0200 Cedric Blancher wrote: > >> On 2 September 2012 06:04, Glenn Fowler <g...@research.att.com> wrote: > >> > > >> > is there any rationale for there being no *at() variant for > >> > > >> > chdir() > >> > truncate() > > > >> If I remember it right from the old POSIX conf calls: Everything which > >> requires to access a file's content and has a f* function should go > >> through openat()+f*(). In this case this means you'd have to call > >> openat() to get a file handle and use ftruncate(). > > > >> chdir() has explicitly no at version because the same basic rule > >> (replace "file's content" with "directory's content") applies: Use > >> openat() with O_SEARCH+fchdir(). It's two syscalls but it's almost > >> having identical performance. And you always have the directory fd > >> around for later usage :) > > > > thanks > > and I'll keep that "2 syscalls almost the same as 1" in my back pocket
> No, no, I didn't mean that as general rule. Just the combination of > openat() and fchdir() is fast because fchdir() has almost nothing todo > except swapping some pointers. I figured that _______________________________________________ ast-developers mailing list ast-developers@research.att.com https://mailman.research.att.com/mailman/listinfo/ast-developers
