From: Razvan Cojocaru Date: Fri, 28 Nov 2014 12:26:48 +0000 (+0200) Subject: xenstore: Clarify xs_open() semantics X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4044 X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=13dc6bf0430eedc3422d81b87764c31e59a73b1f;p=xen.git xenstore: Clarify xs_open() semantics Added to the xs_open() comments in xenstore.h. The text has been taken almost verbatim from a xen-devel email by Ian Campbell, and confirmed as accurate by Ian Jackson. Suggested-by: Ian Campbell Signed-off-by: Razvan Cojocaru Acked-by: Ian Jackson --- diff --git a/tools/xenstore/include/xenstore.h b/tools/xenstore/include/xenstore.h index fdf5e764ba..b4b113edd8 100644 --- a/tools/xenstore/include/xenstore.h +++ b/tools/xenstore/include/xenstore.h @@ -59,10 +59,20 @@ typedef uint32_t xs_transaction_t; /* On failure, these routines set errno. */ /* Open a connection to the xs daemon. - * Attempts to make a connection over the socket interface, + * Attempts to make a connection over the socket interface, * and if it fails, then over the xenbus interface. * Mode 0 specifies read-write access, XS_OPEN_READONLY for * read-only access. + * + * * Connections made with xs_open(0) (which might be shared page or + * socket based) are only guaranteed to work in the parent after + * fork. + * * Connections made with xs_open(XS_OPEN_SOCKETONLY) will be usable + * in either the parent or the child after fork, but not both. + * * xs_daemon_open*() and xs_domain_open() are deprecated synonyms + * for xs_open(0). + * * XS_OPEN_READONLY has no bearing on any of this. + * * Returns a handle or NULL. */ struct xs_handle *xs_open(unsigned long flags);