Commit: patch 9.2.1039: MS-Windows: Unix domain socket channels fail

[Christian Brabandt]

patch 9.2.1039: MS-Windows: Unix domain socket channels fail

Commit: https://github.com/vim/vim/commit/7808a184d90b198c4bda9a097319eb8a8e507883
Author: Hirohito Higashi <h.eas...@gmail.com>
Date: Mon Sep 7 20:01:09 2026 +0000

patch 9.2.1039: MS-Windows: Unix domain socket channels fail

Problem: On MS-Windows, ch_listen() and ch_open() with a "unix:"
address fail with E1573 unless a TCP channel was used before
in the same Vim process.
Solution: Initialize Winsock before creating a Unix domain socket, as
is done for TCP sockets (Hirohito Higashi).

closes: #21242

Co-Authored-By: Claude Fable 5.1 <nor...@anthropic.com>
Signed-off-by: Hirohito Higashi <h.eas...@gmail.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/src/channel.c b/src/channel.c
index 3fc9120b3..a8ffe2b30 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -838,6 +838,10 @@ channel_open_unix(
return NULL;
}

+#ifdef MSWIN
+ channel_init_winsock();
+#endif
+
channel = add_channel();
if (channel == NULL)
{
@@ -1640,6 +1644,10 @@ channel_listen_unix(
return NULL;
}

+#ifdef MSWIN
+ channel_init_winsock();
+#endif
+
channel = add_channel();
if (channel == NULL)
{
diff --git a/src/testdir/test_channel.vim b/src/testdir/test_channel.vim
index 6aab5b166..9d2eb5a08 100644
--- a/src/testdir/test_channel.vim
+++ b/src/testdir/test_channel.vim
@@ -2900,6 +2900,39 @@ func Test_listen_info_no_hostname()
call ch_close(ch)
endfunc

+" A Unix domain socket must work when it is the first socket used in a Vim
+" process, so run it in a separate Vim.
+func Test_listen_unix_first_socket()
+ let sockpath = fnamemodify('Xlistensock', ':p')
+ if len(sockpath) >= 100
+ throw 'Skipped: socket path is too long'
+ endif
+ let after =<< trim eval [CODE]
+ func OnAccept(ch, addr)
+ call ch_setoptions(a:ch, #{{mode: 'raw'}})
+ call add(g:result, 'accept ' .. a:addr)
+ endfunc
+ let g:result = []
+ let server = ch_listen('unix:{sockpath}', #{{callback: 'OnAccept'}})
+ call add(g:result, 'listen ' .. ch_status(server))
+ let client = ch_open('unix:{sockpath}', #{{mode: 'raw'}})
+ call add(g:result, 'open ' .. ch_status(client))
+ let cnt = 0
+ while len(g:result) < 3 && cnt < 500
+ sleep 10m
+ let cnt += 1
+ endwhile
+ call writefile(g:result, 'Xlistenresult')
+ qall!
+ [CODE]
+ if RunVim([], after, '')
+ call assert_equal(['accept unix:anonymous', 'listen open', 'open open'],
+ \ sort(readfile('Xlistenresult')))
+ endif
+ call delete('Xlistenresult')
+ call delete('Xlistensock')
+endfunc
+
func Test_channel_lsp_mode()
" The channel lsp mode test is flaky and gives the same error.
let g:giveup_same_error = 0
diff --git a/src/version.c b/src/version.c
index 14763ece9..a36d127d5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -763,6 +763,8 @@ static char *(features[]) =

static int included_patches[] =
{ /* Add new patch number below this line */
+/**/
+ 1039,
/**/
1038,
/**/