Problem:
A `--listen` path longer than the system socket path limit (~104 bytes on
macOS, 108 on Linux) is silently truncated by `uv_pipe_bind()`. Nvim either
serves a socket at a different path than `v:servername` reports, or fails with
an error that blames the full untruncated path (confusing):
nvim: Failed to --listen: address already in use: "<full path>"
Steps to reproduce:
$ nvim --listen /var/folders/g7/9y_ydbnj2fs_fvp8xf44p8gc0000gn/T//nvim/-Users-rpatterson-Projects-src-github.com-neovide-neovide --embed -p
nvim: Failed to --listen: address already in use: "/var/folders/g7/9y_ydbnj2fs_fvp8xf44p8gc0000gn/T//nvim/-Users-rpatterson-Projects-src-github.com-neovide-neovide"
$ ls /var/folders/g7/9y_ydbnj2fs_fvp8xf44p8gc0000gn/T//nvim/-Users-rpatterson-Projects-src-github.com-neovide-neovide
"/var/folders/g7/9y_ydbnj2fs_fvp8xf44p8gc0000gn/T//nvim/-Users-rpatterson-Projects-src-github.com-neovide-neovide": No such file or directory (os error 2)
$ ls -l /var/folders/g7/9y_ydbnj2fs_fvp8xf44p8gc0000gn/T//nvim/
srwxr-xr-x@ - rpatterson 31 Mar 10:24 -Users-rpatterson-Projects-src-github.com-neovid
Solution:
Bind with `uv_pipe_bind2()` and `UV_PIPE_NO_TRUNCATE` (libuv 1.46+), so
a too-long path fails up front with the actual reason:
nvim: Failed to --listen: invalid argument: "<full path>"
(cherry picked from commit de141b4679)
Problem:
`:restart` does not preserve window layout, etc.
Solution:
- Change `:restart` to save/restore a session automatically.
- Introduce "bang" variant `:restart!` to restart *without* session
save/restore.
- Introduce `v:startreason`.
- `ZR` maps to `:restart!`.
(cherry picked from commit 845b66dd4a)
Problem:
It's clumsy for scripts to handle a "restart", without custom mappings or
global vars.
Solution:
Introduce `v:startreason`
(cherry picked from commit ae426ee465)
Change --embed so that the first UI can be on non-stdio channel even if
neither --headless nor --listen is passed.
(cherry picked from commit a3a48392c5)
Problem:
Crashed Nvim leaves socket files. Subsequent starts fail with "address already in use".
Solution:
On bind failure, test socket liveness via connect(). Remove if stale, retry bind().
Fixes#36581
Problem:
If $NVIM_APPNAME is a relative dir path, Nvim fails to start its
primary/default server, and `v:servername` is empty.
Root cause is d34c64e342, but this wasn't
noticed until 96128a5076 started reporting the error more loudly.
Solution:
- `server_address_new`: replace slashes "/" in the appname before using
it as a servername.
- `vim_mktempdir`: always prefer the system-wide top-level "nvim.user/"
directory. That isn't intended to be specific to NVIM_APPNAME; rather,
each *subdirectory* ("nvim.user/xxx") is owned by each Nvim instance.
Nvim "apps" can be identified by the server socket(s) stored in those
per-Nvim subdirs.
fix#30256
