On Sun, Apr 28, 2013 at 02:36:24PM +0100, Ian Lynagh wrote:
However, if we are on a platform that supports vfork, then we can pass information from the child process back to the parent process as they share address space.
AIUI the POSIX standard at least does not guarantee this behaviour – it's perfectly OK in theory for vfork to be equal to fork, and more generally the behaviour of a vfork which edits its parent's memory is seemingly unspecified. I don't know if Linux provides more guarantees than that, but if we're relying on nonstandard behaviour this fact should be at least commented. I think the "right" way to do this is creating a pipe() beforehand and then using conventional-fork, and writing to the pipe if anything goes wrong. I'm not an expert though! -- Ben