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Gio.UnixFDList

class — extends GObject.Object

A GUnixFDList contains a list of file descriptors. It owns the file descriptors that it contains, closing them when finalized.

It may be wrapped in a GUnixFDMessage and sent over a Socket in the G_SOCKET_FAMILY_UNIX family by using Socket.send_message and received using Socket.receive_message.

Before 2.74, <gio/gunixfdlist.h> belonged to the UNIX-specific GIO interfaces, thus you had to use the gio-unix-2.0.pc pkg-config file when using it.

Since 2.74, the API is available for Windows.

Constructors

new

@classmethod
def new(cls) -> UnixFDList

Creates a new UnixFDList containing no file descriptors.

new_from_array

@classmethod
def new_from_array(cls, fds: list[int]) -> UnixFDList

Creates a new UnixFDList containing the file descriptors given in fds. The file descriptors become the property of the new list and may no longer be used by the caller. The array itself is owned by the caller.

Each file descriptor in the array should be set to close-on-exec.

If n_fds is -1 then fds must be terminated with -1.

Parameters:

  • fds — the initial list of file descriptors

Methods

append

def append(self, fd: int) -> int

Adds a file descriptor to list.

The file descriptor is duplicated using dup(). You keep your copy of the descriptor and the copy contained in list will be closed when list is finalized.

A possible cause of failure is exceeding the per-process or system-wide file descriptor limit.

The index of the file descriptor in the list is returned. If you use this index with UnixFDList.get then you will receive back a duplicated copy of the same file descriptor.

Parameters:

  • fd — a valid open file descriptor

get

def get(self, index_: int) -> int

Gets a file descriptor out of list.

index_ specifies the index of the file descriptor to get. It is a programmer error for index_ to be out of range; see UnixFDList.get_length.

The file descriptor is duplicated using dup() and set as close-on-exec before being returned. You must call close() on it when you are done.

A possible cause of failure is exceeding the per-process or system-wide file descriptor limit.

Parameters:

  • index_ — the index into the list

get_length

def get_length(self) -> int

Gets the length of list (ie: the number of file descriptors contained within).

peek_fds

def peek_fds(self) -> list[int]

Returns the array of file descriptors that is contained in this object.

After this call, the descriptors remain the property of list. The caller must not close them and must not free the array. The array is valid only until list is changed in any way.

If length is non-None then it is set to the number of file descriptors in the returned array. The returned array is also terminated with -1.

This function never returns None. In case there are no file descriptors contained in list, an empty array is returned.

steal_fds

def steal_fds(self) -> list[int]

Returns the array of file descriptors that is contained in this object.

After this call, the descriptors are no longer contained in list. Further calls will return an empty list (unless more descriptors have been added).

The return result of this function must be freed with GLib.free. The caller is also responsible for closing all of the file descriptors. The file descriptors in the array are set to close-on-exec.

If length is non-None then it is set to the number of file descriptors in the returned array. The returned array is also terminated with -1.

This function never returns None. In case there are no file descriptors contained in list, an empty array is returned.