Phonet: provide pipe socket option to retrieve the pipe identifier
User-space sometimes needs this information. In particular, the GPRS
context or the AT commands pipe setups may use the pipe handle as a
reference.
This removes the settable pipe handle with CONFIG_PHONET_PIPECTRLR.
It did not handle error cases correctly. Furthermore, the kernel
*could* implement a smart scheme for allocating handles (if ever
needed), but userspace really cannot.
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/phonet.txt b/Documentation/networking/phonet.txt
index 24ad2ad..cacac96 100644
--- a/Documentation/networking/phonet.txt
+++ b/Documentation/networking/phonet.txt
@@ -181,6 +181,10 @@
interface index of the network interface created by PNPIPE_ENCAP,
or zero if encapsulation is off.
+ PNPIPE_HANDLE is a read-only integer value. It contains the underlying
+ identifier ("pipe handle") of the pipe. This is only defined for
+ socket descriptors that are already connected or being connected.
+
Phonet Pipe-controller Implementation
-------------------------------------
@@ -199,9 +203,6 @@
The implementation adds socket options at SOL_PNPIPE level:
- PNPIPE_PIPE_HANDLE
- It accepts an integer argument for setting value of pipe handle.
-
PNPIPE_ENABLE accepts one integer value (int). If set to zero, the pipe
is disabled. If the value is non-zero, the pipe is enabled. If the pipe
is not (yet) connected, ENOTCONN is error is returned.