xx_linux_foreign_toplevel_pidfd_v1
The purpose of this protocol is to provide a way for Linux based compositors to identify the process a toplevel belongs to.
This protocol depends on the ext-foreign-toplevel-list protocol.
The compositor may choose to restrict this protocol to a special client launched by the compositor itself or expose it to all clients, this is compositor policy.
The key words "must", "must not", "required", "shall", "shall not", "should", "should not", "recommended", "may", and "optional" in this document are to be interpreted as described in IETF RFC 2119.
Warning! The protocol described in this file is currently in the experimental phase. Backwards incompatible major versions of the protocol are to be expected. Exposing this protocol without an opt-in mechanism is discouraged.
This interface allows a compositor to announce support for supplying pidfds for the processes of toplevels to the client.
destroy()
Using this request a client can tell the server that it is not going to use the xx_linux_foreign_toplevel_pidfd_manager_v1 object anymore.
Any objects already created through this instance are not affected.
get_pidfd(handle: object<ext_foreign_toplevel_list_v1>, id: new_id<xx_linux_foreign_toplevel_pidfd_v1>)
Argument | Type | Description |
|---|---|---|
| handle | object<ext_foreign_toplevel_list_v1> | |
| id | new_id<xx_linux_foreign_toplevel_pidfd_v1> |
This creates a new linux_foreign_toplevel_pidfd object for the ext_foreign_toplevel_list_v1. The created object can then be used to receive pidfds of procceses that belong to toplevels.
xx_linux_foreign_toplevel_pidfd_v1
After a client binds the xx_linux_foreign_toplevel_pidfd_v1 the compositor will send pidfds for all existing toplevels and each new toplevel window announced via the ext_foreign_toplevel_list_v1.toplevel event will also send a pidfd.
If a compositor implementation sends the xx_foreign_toplevel_pidfd_v1.finished event, the compositor must not send any more xx_linux_foreign_toplevel_pidfd_v1.pidfd events.
A pidfd references the toplevel's process identifier (pid) via a file descriptor see pidfd_open(1).
destroy()
Using this request a client can tell the server that it is not going to use the xx_linux_foreign_toplevel_pidfd_v1 object anymore.
pidfd(toplevel: object<ext_foreign_toplevel_handle_v1>, pidfd: fd)
Argument | Type | Description |
|---|---|---|
| toplevel | object<ext_foreign_toplevel_handle_v1> | |
| pidfd | fd | pid fd |
This event is emitted whenever a new toplevel window is created. It is emitted for all toplevels, regardless of the app that has created them.
The pidfd refers to the toplevel's process identifier.
finished()
This event indicates that the compositor is done sending events to this object. The client should destroy the object. See xx_foreign_toplevel_pidfd_v1.destroy for more information.
Compositor Support
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