[SOLVED] X Can't open display: :0

Alfred-Augustus · 05-14-2022, 11:18 PM

Quote:

Originally Posted by henca

Is there any difference in the output from "xauth list" when you can open new windows and after it fails?
regards Henrik

I just got the Can't-open-display error again.

Immediately after noticing the error, I did "xauth list", and got...

Code:

slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  xxxx
slacktp/unix:0  MIT-MAGIC-COOKIE-1  xxxx

xxxx are numbers and characters.

After I restarted FVWM, I went back and did "xauth list" again, and got...

Code:

slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  xxxx
slacktp/unix:0  MIT-MAGIC-COOKIE-1  xxxx
localhost.localdomain/unix:0  MIT-MAGIC-COOKIE-1  xxxx

Does this help?

Thanks!

henca · 05-15-2022, 08:00 AM

Quote:

Originally Posted by Alfred-Augustus

I just got the Can't-open-display error again.

Immediately after noticing the error, I did "xauth list", and got...

Code:

slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  xxxx
slacktp/unix:0  MIT-MAGIC-COOKIE-1  xxxx

xxxx are numbers and characters.

After I restarted FVWM, I went back and did "xauth list" again, and got...

Code:

slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  xxxx
slacktp/unix:0  MIT-MAGIC-COOKIE-1  xxxx
localhost.localdomain/unix:0  MIT-MAGIC-COOKIE-1  xxxx

Does this help?

Just to make sure, you should check from within the same X session before and after the problem comes. However, we can already see that one row for localhost is missing when X is broken. One thing to also look for is if those xxxx are the same numbers for all 3 rows and if they are still exactly the same numbers when X stops working. I can't say for sure if that localhost row is of any importance, I don't have that row on my Slackware 14.2 system with working X.

One more thing to compare might be the output of:

ls -al ~/.Xauthority*

Before and after X stops working. Did something tamper with that file?

regards Henrik

henca · 05-15-2022, 08:07 AM

Quote:

Originally Posted by Alfred-Augustus

But there is a always this message after I execute startx...

Code:

tpbox> startx
xauth:  file /home/tpbox/.serverauth.xxxx does not exist

In my previous message I wrote you should look for files called ~/.Xauthority* but maybe you should look for files called ~/.serverauth* instead.

The "program" /usr/bin/startx is only a simple script and it removes that file before calling xauth so the warning from xauth about the file missing is probably harmless.

Code:

    # create a file with auth information for the server. ':0' is a dummy.
    xserverauthfile=$HOME/.serverauth.$$
    trap "rm -f '$xserverauthfile'" HUP INT QUIT ILL TRAP KILL BUS TERM
    xauth -q -f "$xserverauthfile" << EOF
add :$dummy . $mcookie
EOF

regards Henrik

henca · 05-16-2022, 12:15 PM

One more thing to check before and after X stops working:

ls -al /tmp/.X*

Maybe you have something running as root which cleans up stuff from the /tmp directory? That could case X to stop working.

regards Henrik

Alfred-Augustus · 05-16-2022, 10:03 PM

Quote:

Originally Posted by henca

One more thing to check before and after X stops working:

ls -al /tmp/.X*

Maybe you have something running as root which cleans up stuff from the /tmp directory? That could case X to stop working.

regards Henrik

Hi,
I saved the files .serverauth.xxxx and the output to "xauth list", before the problem occurred.
They are the *.pre files. The *.post files are output immediately after I discovered the problem (before quiting X).
The tmp.pre and tmp.post are outputs to "ls -al /tmp/.X*"

Code:

$ ls
serverauth.1195.post  tmp.post  xauth-list.post
serverauth.1195.pre   tmp.pre   xauth-list.pre
$
$ diff serverauth.1195.pre serverauth.1195.post 
$ 
$ diff tmp.pre tmp.post 
6c6
< drwxrwxrwt 15 root root  4096 May 17 10:42 ..
---
> drwxrwxrwt 16 root root  4096 May 17 10:50 ..
$
$ diff xauth-list.pre xauth-list.post 
$

Code:

$ cat serverauth.1195.pre 
slacktp.localhost0MIT-MAGIC-COOKIE-1��p'Yp�)�,W�tslacktp.localhost1MIT-MAGIC-COOKIE-1��΄�߯�����
              �# 
$ cat serverauth.1195.post
slacktp.localhost0MIT-MAGIC-COOKIE-1��p'Yp�)�,W�tslacktp.localhost1MIT-MAGIC-COOKIE-1��΄�߯�����
              �#

Code:

$ cat xauth-list.pre 
slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  9d861670275970e4042913a12c57d574
slacktp/unix:0  MIT-MAGIC-COOKIE-1  85364fc4cd14f46bc986673245d6134a
$ 
$ cat xauth-list.post
slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  9d861670275970e4042913a12c57d574
slacktp/unix:0  MIT-MAGIC-COOKIE-1  85364fc4cd14f46bc986673245d6134a

Code:

$ cat tmp.pre 
-r--r--r-- 1 root users   11 May 17 10:42 /tmp/.X0-lock

/tmp/.X11-unix:
total 8
drwxrwxrwt  2 root root  4096 May 17 10:42 .
drwxrwxrwt 15 root root  4096 May 17 10:42 ..
srwxrwxrwx  1 root users    0 May 17 10:42 X0
$ 
$
$ cat tmp.post
-r--r--r-- 1 root users   11 May 17 10:42 /tmp/.X0-lock

/tmp/.X11-unix:
total 8
drwxrwxrwt  2 root root  4096 May 17 10:42 .
drwxrwxrwt 16 root root  4096 May 17 10:50 ..
srwxrwxrwx  1 root users    0 May 17 10:42 X0
$

Alfred-Augustus · 05-16-2022, 10:12 PM

Hi

I notice now the error message is different. In my 1st post, I showed I was getting a "no protocol specified" error. Now I am getting a "Invadid MIT-MAGIC-COOKIE-1 key Error".

Code:

$ xclock
Invalid MIT-MAGIC-COOKIE-1 keyError: Can't open display: :0
$
$ xev
Invalid MIT-MAGIC-COOKIE-1 keyxev:  unable to open display ':0'
$ 
$ 
$ xterm
Invalid MIT-MAGIC-COOKIE-1 keyxterm: Xt error: Can't open display: :0
$

Perhaps it is due to an update I did yesterday.

Code:

# slackpkg update
# slackpkg install-new
# slackpkg upgrade-all
# slackpkg clean-system

Alfred-Augustus · 05-16-2022, 10:35 PM

The problem is happening alot today (3 times already today).

I am suspecting it has something to do with my laptop today being on only battery-power.
And I closed the lid with power-on (sleep mode) a few times.
Usually, I am near a wall-outlet, in charging mode.

Can the laptop's power management mess with the X authority?

p.s. I have not installed any software.

zeebra · 05-17-2022, 01:23 AM

Quote:

Originally Posted by Alfred-Augustus

The problem is happening alot today (3 times already today).

I am suspecting it has something to do with my laptop today being on only battery-power.
And I closed the lid with power-on (sleep mode) a few times.
Usually, I am near a wall-outlet. So most of the time, it is in charging mode.

Can the laptop's power management mess with the X authority?

p.s. I have not installed any software.

Well, it's difficult to understand why this happens. But perhaps it would be interesting to see if anything would change if you start xorg and your desktop with a display manager instead of using startx. Like SDDM or something like that.

Things normally shouldn't interfere with MIT-MAGIC-COOKIE/Xauthority, but it's possible in theory.

Quote:

Originally Posted by Alfred-Augustus

But there is a always this message after I execute startx...

Code:

$ startx
xauth:  file /home/tpbox/.serverauth.xxxx does not exist

I actually noticed I also have a message like this in my startx, and my X session/desktop works just fine. So that's not relevant to the problem.

Alfred-Augustus · 05-17-2022, 05:43 AM

Quote:

Originally Posted by zeebra

Well, it's difficult to understand why this happens. But perhaps it would be interesting to see if anything would change if you start xorg and your desktop with a display manager instead of using startx. Like SDDM or something like that.

I was looking at the installation documentation again, and I saw that I missed one step during post-install of Slackware. The documentation says I might need to do a

Code:

$ X -configure

, but I never did. When I execute this command just now, I get an error.

Code:

$ X -configure 

X.Org X Server 1.20.14
X Protocol Version 11, Revision 0
Build Operating System: Slackware 15.0 Slackware Linux Project
Current Operating System: Linux slacktp 5.15.38 #1 SMP PREEMPT Mon May 9 15:36:07 CDT 2022 x86_64
Kernel command line: BOOT_IMAGE=generic-5.15.38 ro root=805
Build Date: 26 December 2021  04:51:07PM
 
Current version of pixman: 0.40.0
        Before reporting problems, check http://wiki.x.org
        to make sure that you have the latest version.
Markers: (--) probed, (**) from config file, (==) default setting,
        (++) from command line, (!!) notice, (II) informational,
        (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
(==) Log file: "/var/log/Xorg.0.log", Time: Tue May 17 18:36:17 2022
List of video drivers:
        amdgpu
        apm
        ark
        ast
        ati
        chips
        cirrus
        dummy
        glint
        i128
        i740
        intel
        mach64
        mga
        neomagic
        nouveau
        nv
        openchrome
        r128
        radeon
        rendition
        s3
        s3virge
        savage
        siliconmotion
        sis
        sisusb
        tdfx
        tga
        trident
        tseng
        v4l
        vboxvideo
        vmware
        voodoo
        modesetting
        vesa
(++) Using config file: "/root/xorg.conf.new"
(==) Using config directory: "/etc/X11/xorg.conf.d"
(==) Using system config directory "/usr/share/X11/xorg.conf.d"


Xorg detected your mouse at device /dev/input/mice.
Please check your config if the mouse is still not
operational, as by default Xorg tries to autodetect
the protocol.

Your xorg.conf file is /root/xorg.conf.new

To test the server, run 'X -config /root/xorg.conf.new'

(EE) Server terminated with error (2). Closing log file.

Does this mean anything?

zeebra · 05-17-2022, 06:01 AM

Quote:

Originally Posted by Alfred-Augustus

I was looking at the installation documentation again, and I saw that I missed one step during post-install of Slackware. The documentation says I might need to do a

Code:

$ X -configure

, but I never did. When I execute this command just now, I get an error.

Code:

$ X -configure

Does this mean anything?

No. You don't have to and probably shouldn't run that unless you need to and know why you need it.

I don't know how you start X with SDDM, but you should give it a try. I'm sure someone here knows how to correctly start X through SDDM. It would help narrow down the issue if you did. Check if you have the same issue if you launch X (correctly) with SDDM.

Perhaps starting SDDM is as simple as switching to runlevel 4.

henca · 05-17-2022, 12:01 PM

Quote:

Originally Posted by Alfred-Augustus

Hi,
I saved the files .serverauth.xxxx and the output to "xauth list", before the problem occurred.
They are the *.pre files. The *.post files are output immediately after I discovered the problem (before quiting X).
The tmp.pre and tmp.post are outputs to "ls -al /tmp/.X*"

Code:

$ ls
serverauth.1195.post  tmp.post  xauth-list.post
serverauth.1195.pre   tmp.pre   xauth-list.pre
$
$ diff serverauth.1195.pre serverauth.1195.post 
$ 
$ diff tmp.pre tmp.post 
6c6
< drwxrwxrwt 15 root root  4096 May 17 10:42 ..
---
> drwxrwxrwt 16 root root  4096 May 17 10:50 ..
$
$ diff xauth-list.pre xauth-list.post

That difference is OK, it only shows that the directory above (your home directory) has changed. The important thing is that any files in that directory has not been modified.

Quote:

Originally Posted by Alfred-Augustus

Code:

$ cat serverauth.1195.pre 
slacktp.localhost0MIT-MAGIC-COOKIE-1��p'Yp�)�,W�tslacktp.localhost1MIT-MAGIC-COOKIE-1��΄�߯�����
              �# 
$ cat serverauth.1195.post
slacktp.localhost0MIT-MAGIC-COOKIE-1��p'Yp�)�,W�tslacktp.localhost1MIT-MAGIC-COOKIE-1��΄�߯�����
              �#

They look binary, but from the output of "ls -al" we know that it hasn't been modified.

Quote:

Originally Posted by Alfred-Augustus

Code:

$ cat xauth-list.pre 
slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  9d861670275970e4042913a12c57d574
slacktp/unix:0  MIT-MAGIC-COOKIE-1  85364fc4cd14f46bc986673245d6134a
$ 
$ cat xauth-list.post
slacktp.localhost/unix:0  MIT-MAGIC-COOKIE-1  9d861670275970e4042913a12c57d574
slacktp/unix:0  MIT-MAGIC-COOKIE-1  85364fc4cd14f46bc986673245d6134a

Again, this looks fine. You have the same xauth settings before and after the problem occurs.

Quote:

Originally Posted by Alfred-Augustus

Code:

$ cat tmp.pre 
-r--r--r-- 1 root users   11 May 17 10:42 /tmp/.X0-lock

/tmp/.X11-unix:
total 8
drwxrwxrwt  2 root root  4096 May 17 10:42 .
drwxrwxrwt 15 root root  4096 May 17 10:42 ..
srwxrwxrwx  1 root users    0 May 17 10:42 X0
$ 
$
$ cat tmp.post
-r--r--r-- 1 root users   11 May 17 10:42 /tmp/.X0-lock

/tmp/.X11-unix:
total 8
drwxrwxrwt  2 root root  4096 May 17 10:42 .
drwxrwxrwt 16 root root  4096 May 17 10:50 ..
srwxrwxrwx  1 root users    0 May 17 10:42 X0
$

Again, this looks fine. The socket X0 is still there and the time stamps are still the same.

It is a little sad that everything looks so good, because none of these outputs explains your problems.

Instead of guessing about causes we could make an attempt to debug the problem with strace. For this, we should use some program which opens the display but does not put a window on the display as those window events might give a lot of noise in the strace output. One good example of such a program is xdpyinfo, but xdpyinfo in itself does give a lot of noise as output. For that reason I think that the command of choice will be "xrdb -query" which only gives a few rows as output and does not open any window.

Could you try:

strace xrdb -query >& /tmp/xrdb.log.pre

and

strace xrdb -query >& /tmp/xrdb.log.post

before and after X fails? My guess is that the command before will result in a log file with about 200 lines and after failure a shorter log file. Maybe the differences between these logs can give some clue about what fails.

regards Henrik

Alfred-Augustus · 05-18-2022, 02:03 AM

Quote:

Originally Posted by henca

Could you try:

strace xrdb -query >& /tmp/xrdb.log.pre

and

strace xrdb -query >& /tmp/xrdb.log.post

before and after X fails?

regards Henrik

Here they are...

Code:

 
$ 
$ cat xrdb.log.pre 
execve("/usr/bin/xrdb", ["xrdb", "-query"], 0x7fffa186fb98 /* 46 vars */) = 0
brk(NULL)                               = 0x1382000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=204128, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 204128, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f6f8ed0e000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXmuu.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@!\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 14048) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=18592, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f6f8ed0c000
mmap(NULL, 20648, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8ed06000
mmap(0x7f6f8ed08000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8ed08000
mmap(0x7f6f8ed09000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f6f8ed09000
mmap(0x7f6f8ed0a000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f6f8ed0a000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libX11.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0`\t\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 1285424) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=1310240, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 1314208, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8ebc5000
mprotect(0x7f6f8ebe3000, 1167360, PROT_NONE) = 0
mmap(0x7f6f8ebe3000, 552960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e000) = 0x7f6f8ebe3000
mmap(0x7f6f8ec6a000, 610304, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xa5000) = 0x7f6f8ec6a000
mmap(0x7f6f8ed00000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x13a000) = 0x7f6f8ed00000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\200A\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0;\0\0\0\0\0\0\0"..., 48, 848) = 48
pread64(3, "\4\0\0\0\20\0\0\0\1\0\0\0GNU\0\0\0\0\0\3\0\0\0\2\0\0\0\0\0\0\0", 32, 896) = 32
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=2168056, ...}, AT_EMPTY_PATH) = 0
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 1959240, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8e9e6000
mmap(0x7f6f8ea08000, 1433600, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x22000) = 0x7f6f8ea08000
mmap(0x7f6f8eb66000, 327680, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x180000) = 0x7f6f8eb66000
mmap(0x7f6f8ebb6000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1cf000) = 0x7f6f8ebb6000
mmap(0x7f6f8ebbc000, 34120, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f6f8ebbc000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libxcb.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\20\327\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 157256) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=162752, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 165000, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8e9bd000
mmap(0x7f6f8e9ca000, 69632, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd000) = 0x7f6f8e9ca000
mmap(0x7f6f8e9db000, 36864, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e000) = 0x7f6f8e9db000
mmap(0x7f6f8e9e4000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x26000) = 0x7f6f8e9e4000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\21\0\0\0\0\0\0"..., 832) = 832
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=18008, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 16688, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8e9b8000
mmap(0x7f6f8e9b9000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7f6f8e9b9000
mmap(0x7f6f8e9ba000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8e9ba000
mmap(0x7f6f8e9bb000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8e9bb000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXau.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\21\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 9136) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=14512, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 16664, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8e9b3000
mmap(0x7f6f8e9b4000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7f6f8e9b4000
mmap(0x7f6f8e9b5000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8e9b5000
mmap(0x7f6f8e9b6000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8e9b6000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXdmcp.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\"\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\1\0\0\0\0\0\0\0"..., 48, 23040) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=26808, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f6f8e9b1000
mmap(NULL, 28936, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f6f8e9a9000
mmap(0x7f6f8e9ab000, 8192, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f6f8e9ab000
mmap(0x7f6f8e9ad000, 8192, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4000) = 0x7f6f8e9ad000
mmap(0x7f6f8e9af000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x5000) = 0x7f6f8e9af000
close(3)                                = 0
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f6f8e9a6000
arch_prctl(ARCH_SET_FS, 0x7f6f8e9a6740) = 0
mprotect(0x7f6f8ebb6000, 16384, PROT_READ) = 0
mprotect(0x7f6f8e9af000, 4096, PROT_READ) = 0
mprotect(0x7f6f8e9b6000, 4096, PROT_READ) = 0
mprotect(0x7f6f8e9bb000, 4096, PROT_READ) = 0
mprotect(0x7f6f8e9e4000, 4096, PROT_READ) = 0
mprotect(0x7f6f8ed00000, 4096, PROT_READ) = 0
mprotect(0x7f6f8ed0a000, 4096, PROT_READ) = 0
mprotect(0x408000, 4096, PROT_READ)     = 0
mprotect(0x7f6f8ed6f000, 8192, PROT_READ) = 0
munmap(0x7f6f8ed0e000, 204128)          = 0
brk(NULL)                               = 0x1382000
brk(0x13a3000)                          = 0x13a3000
access("/usr/bin/cpp", X_OK)            = 0
openat(AT_FDCWD, "/dev/null", O_RDONLY) = 3
close(3)                                = 0
socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0) = 3
connect(3, {sa_family=AF_UNIX, sun_path=@"/tmp/.X11-unix/X0"}, 20) = 0
getpeername(3, {sa_family=AF_UNIX, sun_path=@"/tmp/.X11-unix/X0"}, [124 => 20]) = 0
uname({sysname="Linux", nodename="slacktp", ...}) = 0
access("/home/ksiu/.Xauthority", R_OK)  = 0
openat(AT_FDCWD, "/home/ksiu/.Xauthority", O_RDONLY) = 4
newfstatat(4, "", {st_mode=S_IFREG|0600, st_size=180, ...}, AT_EMPTY_PATH) = 0
read(4, "\1\0\0\21slacktp.localhost\0\0010\0\22MIT-MA"..., 4096) = 180
read(4, "", 4096)                       = 0
close(4)                                = 0
getsockname(3, {sa_family=AF_UNIX}, [124 => 2]) = 0
fcntl(3, F_GETFL)                       = 0x2 (flags O_RDWR)
fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK)    = 0
fcntl(3, F_SETFD, FD_CLOEXEC)           = 0
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="l\0\v\0\0\0\22\0\20\0\0\0", iov_len=12}, {iov_base="", iov_len=0}, {iov_base="MIT-MAGIC-COOKIE-1", iov_len=18}, {iov_base="\0\0", iov_len=2}, {iov_base="\23\317\332\201\234g_\323{U\35&\336y\30b", iov_len=16}, {iov_base="", iov_len=0}], 6) = 48
recvfrom(3, "\1\0\v\0\0\0O\2", 8, 0, NULL, NULL) = 8
recvfrom(3, "\260Q\267\0\0\0 \1\377\377\37\0\0\1\0\0\24\0\377\377\1\7\0\0  \10\377\0\0\0\0"..., 2364, 0, NULL, NULL) = 2364
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="b\0\5\0\f\0\0\0BIG-REQUESTS", iov_len=20}], 1) = 20
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\0\1\0\0\0\0\0\1\205\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 32
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="\205\0\1\0", iov_len=4}], 1) = 4
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\0\2\0\0\0\0\0\377\377?\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="7\0\5\0\0\0 \1l\1\0\0\10\0\0\0\377\377\377\0\24\0\6\0l\1\0\0\27\0\0\0"..., iov_len=44}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 44
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\10\4\0*\0\0\0\37\0\0\0\0\0\0\0\247\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 200
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="b\0\5\0\t\0 \1", iov_len=8}, {iov_base="XKEYBOARD", iov_len=9}, {iov_base="\0\0\0", iov_len=3}], 3) = 20
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\0\5\0\0\0\0\0\1\207U\211\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="\207\0\2\0\1\0\0\0", iov_len=8}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 8
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\1\6\0\0\0\0\0\1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
uname({sysname="Linux", nodename="slacktp", ...}) = 0
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="c\0\1\0", iov_len=4}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 4
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\33\7\0B\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 296
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
newfstatat(1, "", {st_mode=S_IFREG|0644, st_size=12177, ...}, AT_EMPTY_PATH) = 0
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="<\0\2\0\0\0 \1+\1\1\0", iov_len=12}, {iov_base=NULL, iov_len=0}, {iov_base="", iov_len=0}], 3) = 12
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN}])
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\1\2\t\0\0\0\0\0\f\0\0\1\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=4096}], msg_iovlen=1, msg_controllen=0, msg_flags=0}, 0) = 32
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
recvmsg(3, {msg_namelen=0}, 0)          = -1 EAGAIN (Resource temporarily unavailable)
shutdown(3, SHUT_RDWR)                  = 0
close(3)                                = 0
write(1, "XTerm*background:\tblack\nXTerm*cu"..., 167XTerm*background:  black
XTerm*cursorColor:      magenta
XTerm*foreground:       gray
xterm*font:     -misc-fixed-medium-r-normal--20-200-75-75-c-100-iso8859-1
xterm*scrollBar:        false
) = 167
exit_group(0)                           = ?
+++ exited with 0 +++
$

Code:

$ 
$ cat xrdb.log.post 
execve("/usr/bin/xrdb", ["xrdb", "-query"], 0x7fff00681e58 /* 47 vars */) = 0
brk(NULL)                               = 0x1c55000
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
newfstatat(3, "", {st_mode=S_IFREG|0644, st_size=204128, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 204128, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fc2d9928000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXmuu.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0@!\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 14048) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=18592, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc2d9926000
mmap(NULL, 20648, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d9920000
mmap(0x7fc2d9922000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d9922000
mmap(0x7fc2d9923000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7fc2d9923000
mmap(0x7fc2d9924000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7fc2d9924000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libX11.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0`\t\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 1285424) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=1310240, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 1314208, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d97df000
mprotect(0x7fc2d97fd000, 1167360, PROT_NONE) = 0
mmap(0x7fc2d97fd000, 552960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e000) = 0x7fc2d97fd000
mmap(0x7fc2d9884000, 610304, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xa5000) = 0x7fc2d9884000
mmap(0x7fc2d991a000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x13a000) = 0x7fc2d991a000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\200A\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0;\0\0\0\0\0\0\0"..., 48, 848) = 48
pread64(3, "\4\0\0\0\20\0\0\0\1\0\0\0GNU\0\0\0\0\0\3\0\0\0\2\0\0\0\0\0\0\0", 32, 896) = 32
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=2168056, ...}, AT_EMPTY_PATH) = 0
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 1959240, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d9600000
mmap(0x7fc2d9622000, 1433600, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x22000) = 0x7fc2d9622000
mmap(0x7fc2d9780000, 327680, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x180000) = 0x7fc2d9780000
mmap(0x7fc2d97d0000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1cf000) = 0x7fc2d97d0000
mmap(0x7fc2d97d6000, 34120, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fc2d97d6000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libxcb.so.1", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\20\327\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 157256) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=162752, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 165000, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d95d7000
mmap(0x7fc2d95e4000, 69632, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd000) = 0x7fc2d95e4000
mmap(0x7fc2d95f5000, 36864, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e000) = 0x7fc2d95f5000
mmap(0x7fc2d95fe000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x26000) = 0x7fc2d95fe000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P\21\0\0\0\0\0\0"..., 832) = 832
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=18008, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 16688, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d95d2000
mmap(0x7fc2d95d3000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7fc2d95d3000
mmap(0x7fc2d95d4000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d95d4000
mmap(0x7fc2d95d5000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d95d5000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXau.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\21\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\t\0\0\0\0\0\0\0"..., 48, 9136) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=14512, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 16664, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d95cd000
mmap(0x7fc2d95ce000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7fc2d95ce000
mmap(0x7fc2d95cf000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d95cf000
mmap(0x7fc2d95d0000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d95d0000
close(3)                                = 0
openat(AT_FDCWD, "/usr/lib64/libXdmcp.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\0\"\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\1\300\4\0\0\0\1\0\0\0\0\0\0\0"..., 48, 23040) = 48
newfstatat(3, "", {st_mode=S_IFREG|0755, st_size=26808, ...}, AT_EMPTY_PATH) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc2d95cb000
mmap(NULL, 28936, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fc2d95c3000
mmap(0x7fc2d95c5000, 8192, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fc2d95c5000
mmap(0x7fc2d95c7000, 8192, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4000) = 0x7fc2d95c7000
mmap(0x7fc2d95c9000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x5000) = 0x7fc2d95c9000
close(3)                                = 0
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fc2d95c0000
arch_prctl(ARCH_SET_FS, 0x7fc2d95c0740) = 0
mprotect(0x7fc2d97d0000, 16384, PROT_READ) = 0
mprotect(0x7fc2d95c9000, 4096, PROT_READ) = 0
mprotect(0x7fc2d95d0000, 4096, PROT_READ) = 0
mprotect(0x7fc2d95d5000, 4096, PROT_READ) = 0
mprotect(0x7fc2d95fe000, 4096, PROT_READ) = 0
mprotect(0x7fc2d991a000, 4096, PROT_READ) = 0
mprotect(0x7fc2d9924000, 4096, PROT_READ) = 0
mprotect(0x408000, 4096, PROT_READ)     = 0
mprotect(0x7fc2d9989000, 8192, PROT_READ) = 0
munmap(0x7fc2d9928000, 204128)          = 0
brk(NULL)                               = 0x1c55000
brk(0x1c76000)                          = 0x1c76000
access("/usr/bin/cpp", X_OK)            = 0
openat(AT_FDCWD, "/dev/null", O_RDONLY) = 3
close(3)                                = 0
socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0) = 3
connect(3, {sa_family=AF_UNIX, sun_path=@"/tmp/.X11-unix/X0"}, 20) = 0
getpeername(3, {sa_family=AF_UNIX, sun_path=@"/tmp/.X11-unix/X0"}, [124 => 20]) = 0
uname({sysname="Linux", nodename="localhost.localdomain", ...}) = 0
access("/home/ksiu/.Xauthority", R_OK)  = 0
openat(AT_FDCWD, "/home/ksiu/.Xauthority", O_RDONLY) = 4
newfstatat(4, "", {st_mode=S_IFREG|0600, st_size=180, ...}, AT_EMPTY_PATH) = 0
read(4, "\1\0\0\21slacktp.localhost\0\0010\0\22MIT-MA"..., 4096) = 180
read(4, "", 4096)                       = 0
close(4)                                = 0
getsockname(3, {sa_family=AF_UNIX}, [124 => 2]) = 0
fcntl(3, F_GETFL)                       = 0x2 (flags O_RDWR)
fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK)    = 0
fcntl(3, F_SETFD, FD_CLOEXEC)           = 0
poll([{fd=3, events=POLLIN|POLLOUT}], 1, -1) = 1 ([{fd=3, revents=POLLOUT}])
writev(3, [{iov_base="l\0\v\0\0\0\22\0\20\0\0\0", iov_len=12}, {iov_base="", iov_len=0}, {iov_base="MIT-MAGIC-COOKIE-1", iov_len=18}, {iov_base="\0\0", iov_len=2}, {iov_base="\202q-Z\2\366[\254\246\3562\222+J5\225", iov_len=16}, {iov_base="", iov_len=0}], 6) = 48
recvfrom(3, 0x1c588b0, 8, 0, NULL, NULL) = -1 EAGAIN (Resource temporarily unavailable)
poll([{fd=3, events=POLLIN}], 1, -1)    = 1 ([{fd=3, revents=POLLIN|POLLHUP}])
recvfrom(3, "\0\36\v\0\0\0\10\0", 8, 0, NULL, NULL) = 8
recvfrom(3, "Invalid MIT-MAGIC-COOKIE-1 key\0\0", 32, 0, NULL, NULL) = 32
write(2, "Invalid MIT-MAGIC-COOKIE-1 key", 30Invalid MIT-MAGIC-COOKIE-1 key) = 30
shutdown(3, SHUT_RDWR)                  = 0
close(3)                                = 0
dup(2)                                  = 3
fcntl(3, F_GETFL)                       = 0x8001 (flags O_WRONLY|O_LARGEFILE)
close(3)                                = 0
write(2, "xrdb: Resource temporarily unava"..., 39xrdb: Resource temporarily unavailable
) = 39
write(2, "xrdb: Can't open display ':0'\n", 30xrdb: Can't open display ':0'
) = 30
exit_group(1)                           = ?
+++ exited with 1 +++
$

henca · 05-18-2022, 11:58 AM

Quote:

Originally Posted by Alfred-Augustus

Here they are...

Thanks! Finally a clue which migt explain something:

Quote:

Originally Posted by Alfred-Augustus

Code:

uname({sysname="Linux", nodename="slacktp", ...}) = 0

Code:

uname({sysname="Linux", nodename="localhost.localdomain", ...}) = 0

It seems as if your machine somehow has lost its name. Initially, when X is started, your machine is named slacktp and in your xauth list you get magic cookies which you can use to connect to slacktp. After some time, for some unknown reason, your machine has lost its name slacktp and is only called localhost. You don't have any magic coookies to connect to localhost.

To verify this theory you could try to run the following commands before and after X hangs:

Code:

uname -n

Code:

hostname -v

But why did it happen? I have no idea. Files to study before and after should be /etc/HOSTNAME and /etc/hosts. If you have a public IP adress you might not want to share the unmodified contents of /etc/hosts here.

The output of...

Code:

grep slacktp /etc/hosts

...would be interesting to compare before and after X hangs, but again, you might want to alter the IP adress before posting here.

It would also be interesting to compare the output of:

Code:

/sbin/ifconfig

Maybe, if you lost your IP address asigned to the hostname that could explain why you lost your hostname.

If you somehow lost your IP address I would look for clues for that in the output from:

Code:

dmesg

regards Henrik

Alfred-Augustus · 05-18-2022, 12:54 PM

Quote:

Originally Posted by henca

It seems as if your machine somehow has lost its name. Initially, when X is started, your machine is named slacktp and in your xauth list you get magic cookies which you can use to connect to slacktp. After some time, for some unknown reason, your machine has lost its name slacktp and is only called localhost. You don't have any magic coookies to connect to localhost.

regards Henrik

Hi, during the installation, it asked for "Enter Hostname:". I typed "slacktp".

Then it asked for "Enter domain name:". I typed "localhost".

enorbet · 05-18-2022, 01:06 PM

Fully qualified hostname would be in the format (example) "slacktp.host.net" where the simple hostname would then be "slacktp". In the example, the qualifier "host.net" can be in any desired 2 part naming, like home.net, house.us, flat.uk, etc. The fully qualified name really shouldn't be "foo.localhost" since the template is IIRC "localhost.host.foo". It could be that the order swap is confusing to the system. In any case it is easily solved by an explicit declaration in the fully qualified "/etc/HOSTNAME" file.

If you use ssh, you should enter both the fully qualified and the simple in the appropriate "/etc/hosts*" and "/etc/exports" files.