Tmux is broken in alpine:3.5 docker images

[marcosnils]

I'm getting lost server when trying to run tmux (2.3) in alpine:3.5 (latest) through docker.

I've confirmed that the problem is the alpine image as it works in alpine 3.4 with tmux 2.2. I've tried installing tmux 2.2 in alpine 3.5 and the problem persists.

This is the error message when setting tmux to debug:

1484088612.022883 cmd_find_target: cmdq 0x56431f2e9960, flags 0x2
1484088612.022890 cmd_find_target: s=none
1484088612.022897 cmd_find_target: wl=none
1484088612.022904 cmd_find_target: wp=none
1484088612.022912 cmd_find_target: idx=none
1484088612.022919 preparing -s state: target none
1484088612.022941 fatal: tcgetattr failed: Bad file descriptor

Might be related to #162

[tianon]

Here's some relevant bits from strace too:

57    readlink("/proc/self/fd/0",  <unfinished ...>
58    <... fork resumed> )              = 59
57    <... readlink resumed> "/9", 32)  = 2
59    gettid( <unfinished ...>
57    stat("/9",  <unfinished ...>
59    <... gettid resumed> )            = 59
57    <... stat resumed> 0x7fff778448a0) = -1 ENOENT (No such file or directory)

...

60    recvmsg(7, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="k\0\0\0\24\0
\0\0\10\0\0\0\377\377\377\3779\0\0\0i\0\0\0&\0\0\0\10\0\0\0"..., iov_len=65535}]
, msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 317
60    ioctl(5, TIOCGWINSZ, {ws_row=24, ws_col=80, ws_xpixel=0, ws_ypixel=0}) = 0

60    ioctl(5, TIOCGWINSZ, {ws_row=24, ws_col=80, ws_xpixel=0, ws_ypixel=0}) = 0

60    readlink("/proc/self/fd/5", "/9", 32) = 2
60    stat("/9", 0x7fff778441b0)        = -1 ENOENT (No such file or directory)
60    close(5)                          = 0
60    ioctl(5, TCGETS, 0x7fff77844260)  = -1 EBADF (Bad file descriptor)
60    exit_group(1)                     = ?
57    <... poll resumed> )              = 1 ([{fd=6, revents=POLLIN|POLLHUP}])
60    +++ exited with 1 +++

I wonder if opencontainers/runc#1018 is also related (and potentially the fix for exactly this sort of failure).

[alexellis]

+1 for getting a fix on this.

[marcosnils]

BTW, if you want to reproduce you can use http://play-with-docker.com

[marcosnils]

doesn't seem like an alpine issue. Here's the root problem. moby/moby#8755.