After recent Cygwin update, I get the following error while starting screen
No more PTYs
Sorry, could not find a PTY
[screen is terminating]
What does this error mean? How to solve this?
I searched on google, ppl are suggesting to chmod 666 on /dev/ptmx and /dev/pty* files. I changed them
$ ls -l /dev/ptmx
crw-rw-rw- 1 satram Domain Users 5, 2 Jun 5 13:40 /dev/ptmx
It doesn't help solve the problem. Does anyone why this error happens and how to solve it?
Related
I am trying to use an "Arduboy," based on the Arduino Leonardo, with the Arduino IDE. I cannot upload the example code, however, because of the following error:
avrdude: ser_open(): can't open device "/dev/ttyACM0": Permission denied
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
Before you mark this as a duplicate, here are all of the things I have tried
Adding myself to the dialout group that /dev/ttyACM0 can be modified by
Running chmod a+rw /dev/ttyACM0 every time I plug in the board
Making this udev rule: KERNEL=="ttyACM0", MODE="0666"
None of these things worked. What did work was running it with xdg-su like so: xdg-su -c ./arduino. However, I think it's not the best idea to run the thing as root every time. Is there anything I can do?
I am running openSUSE Tumbleweed.
The Arduino Leonardo based boards interrupt the communication with ttyACM* for a short moment (like logging in and out) during an upload. For some reason, the permissions change during this process. See the output of a repeated ls -l --full-time /dev/ttyACM0 during a failed upload:
crw-rw-rw- 1 root dialout 166, 0 2019-08-11 17:28:31.974025089 +0200 /dev/ttyACM0
ls: cannot access '/dev/ttyACM0': No such file or directory
crw------- 1 root root 166, 0 2019-08-11 17:42:15.523439213 +0200 /dev/ttyACM0
crw-rw---- 1 root dialout 166, 0 2019-08-11 17:42:16.083442857 +0200 /dev/ttyACM0
I also use Tumbleweed. The only workaround that I currently know is to start the Arduino IDE as root.
Go to your arduino's program directory. Open terminal in the directory. Then type ./arduino-linux-setup.sh $USER. After that reboot. You are able to upload code onto your arduino.
We have complaints "from the field" (i.e. from sysadmins installing software) that cygwin "messes up" windows permissions on NTFS (Windows 7/10/2008/2012, etc).
Problem Usecase
The general usecase is this:
Sysadmin launches some 'software installer' from the cygwin bash cmd line
Installer runs fine
Sysadmin tries to start windows services
Result:
Service fails to start
Workaround Steps
These steps seem to get past the problem:
Sysadmin resets ntfs permissions with windows ICACLS command : (in this example "acme" is the newly created directory. This command sets acme and its children to re-inherit permissions from folder "d:\instances"
d:\instances> icacls acme /RESET /T /C /Q
Sysadmin starts service
Result:
Windows service starts
Question
What makes cygwin handle permissions for newly-written files differently than powershell? Is it a matter of a wrong version of umask?
Can the sysadmin take steps in advance to ensure cygwin sets up permissions properly?
thanks in advance
I found the answer here; it refers to this mailing-list letter.
You need to edit Cygwin's /etc/fstab and add "noacl" to the list of mount-options.
To add to the answer of ulathek here is the copy-paste of the two URLs:
First:
How to fix incorrect Cygwin permission in Windows 7
Cygwin started to behave quite strangely after recent updates. I was not able to edit files in vim, because it was complaining that files are read only. Even cp -r didn’t work correctly. Permission of new directory was broken and I was not able to remove it. Pretty weird behavior.
E.g. ls -l
total 2
----------+ 1 georgik None 34 Jul 14 18:09 index.jade
----------+ 1 georgik None 109 Jul 14 17:40 layout.jade
Hm. It is clear that something is wrong with permission. Even owner has no permission on those files.
Output of mount command:
C: on /cygdrive/c type ntfs (binary,posix=0,user,noumount,auto)
I found a solution at cygwin forum. It’s quite easy to fix it.
Open /etc/fstab and enter following line:
none /cygdrive cygdrive binary,noacl,posix=0,user 0 0
Save it. Close all cygwin terminals and start new terminal.
Output of mount:
C: on /cygdrive/c type ntfs (binary,noacl,posix=0,user,noumount,auto)
Output of ls -l
total 2
-rw-r--r-- 1 georgik None 34 Jul 14 18:09 index.jade
-rw-r--r-- 1 georgik None 109 Jul 14 17:40 layout.jade
Second:
7/14/2010 10:57 AM
> Drive Y is a mapping to a network location. Interestingly, ls -l
>> /cygdrive returns:
>> d---------+ 1 ???????? ???????? 24576 2010-07-09 11:18 c
>> drwx------+ 1 Administrators Domain Users 0 2010-07-14 06:58 y
>>
>> The c folder looks weird, the y folder looks correct.
>>
> Try ls -ln /cygdrive. The user and group ownerships on the root of the
> C: drive are most likely not found in your passwd and group files. The
> -n option for ls will print the user and group IDs rather than try to
> look up their names. Unfortunately, I can't think of any way offhand to
> generate the passwd and group entries given only user and group IDs.
> Maybe someone else can comment on that.
>
I think your answer is correct:
$ ls -ln /cygdrive
total 24
d---------+ 1 4294967295 4294967295 24576 2010-07-09 11:18 c
drwx------+ 1 544 10513 0 2010-07-14 11:45 y
I edited my /etc/fstab file (it contained only commented lines) and
added this line at the end of the file:
none /cygdrive cygdrive binary,noacl,posix=0,user 0 0
I closed all my Cygwin processes, opened a new terminal and did an ls-l
on visitor.cpp again:
-rw-r--r-- 1 cory Domain Users 3236 2010-07-11 22:37 visitor.cpp
Success!!! The permissions are now reported as 644 rather than 000 and I
can edit the file with Cygwin vim and not have bogus read-only issues.
Thank you Jeremy.
cory
I messed up the symbolic links of my libblas.so.3
I get the error message:
sudo update-alternatives --list libblas.so.3
update-alternatives: error: cannot stat file '/usr/lib/libblas/libblas.so.3': Too many levels of symbolic links
When I do:
ls -l /usr/lib/libblas/libblas.so.3:
lrwxrwxrwx 1 root root 30 Nov 23 15:15 /usr/lib/libblas/libblas.so.3 -> /etc/alternatives/libblas.so.3
Then, again:
ls -l /etc/alternatives/libblas.so.3
lrwxrwxrwx 1 root root 29 Nov 25 14:36 /etc/alternatives/libblas.so.3 -> /usr/lib/libblas/libblas.so.3
Any help to get ot of this situation would be very much appreciated. I do not know if it is enough information. If not, let me know and I try to provide more. Thanks.
I guess the problem is that /usr/lib/libblas/libblas.so.3 links back to etc/.., however it should point to the actual file. How can I do that?
I had to remove the link in the alternatives directory:
sudo rm /etc/alternatives/libblas.so.3
Then, I recreated the link, but pointnig to a real library file. For that I chose the corresponding one from the atlas package:
sudo ln -s /usr/lib/atlas/atlas-base/libblas.so.3 /etc/alternatives/libblas.so.3
The commands
cd c:/p4
ls -ld . c:/p4 /cygdrive/c/p4
shows
d---------+ 1 jgunter Domain Users 0 Apr 27 18:41 .
d---------+ 1 jgunter Domain Users ? 0 Apr 27 18:41 /cygdrive/c/p4
drwxr-xr-x 1 jgunter Domain Users ? 0 Apr 27 18:41 c:/p4
ls shows the perms I want to see only for files specified with a C:/ path.
I know about getfacl, but I'm hoping there's some ls option that will show me what I want without requiring I spell out absolute paths.
I can do something like:
ls -ld `cygpath -da $#`
but when I'm in a deeply nested folder, the output is cluttered by full pathnames.
DOS path makes cygwin treat the file system as not having ACLs. It means that ls shows the correct ACLs, but the same directory is mounted with different options. Therefore ls doesn't have such an option, you need a workaround.
https://cygwin.com/cygwin-ug-net/ov-new1.7.html states at 1.7.2:
Handle native DOS paths always as if mounted with "posix=0,noacl"
Beside this, I think, that d---------+ is strange. I've tried it on my PC, with 1.7.31 cygwin version, and it shows drwx------+, which is a bit better. I had experienced other bugs and strange behaviour in cygwin ACL handling. I guess there is confusion and some hacks about this. chmod 777 was a good workaround in my case.
For some time, when trying to run dbus gives me the following error, even if I'm logged in as root:
gentoo herman # /etc/init.d/dbus start
* Starting D-BUS system messagebus ...
Failed to start message bus: Failed to bind socket "/var/run/dbus/system_bus_socket": Permission denied
* start-stop-daemon: failed to start `/usr/bin/dbus-daemon' [ !! ]
* ERROR: dbus failed to start
Listing directory:
gentoo herman # ls /var/run/dbus/ -all
ls: nie ma dostępu do /var/run/dbus/system_bus_socket: Brak dostępu
razem 1
drwxr-xr-x 2 root root 88 08-14 16:42 .
drwxr-xr-x 20 root root 824 08-16 16:45 ..
?????????? ? ? ? ? ? system_bus_socket
I tried to delete this file as root via the rm command, but displays the same error.
I have installed :
[ebuild R ] sys-apps/dbus-1.4.14 USE="X static-libs -debug -doc (-selinux) -test"
[ebuild R ] dev-libs/dbus-glib-0.94-r1 USE="static-libs -bash-completion -debug -doc -test"
uname -a :
Linux gentoo 2.6.38-gentoo #6 SMP Fri Jul 1 09:41:37 CEST 2011 x86_64 Intel(R) Core(TM)2 Duo CPU T9400 # 2.53GHz GenuineIntel GNU/Linux
Command "dmesg | grep dbus" nothing displays. Reinstalling dbus also in no way helped. Thanks for any help
Looks like you have corruption in your /var filesystem. Try fsck-ing the file-system.
Also, for a quick workaround you can rename the directory and create a new one, because you won't be able to delete the offending file.
Do as root:
# mv /var/run/dbus /var/run/dbus-broken
# mkdir /var/run/dbus
And start the daemon as usual.
But don't forget the fsck! If there is one error in the FS there may be others lurking around.