I want to check which files does tmux touch when it is launched (not just the list of open files when tmux is running). Strace tmux seemed like the best option.
When trying to redirect the output to a file strace tmux > /tmp/blah. File is empty.
Why does this happen?
How to redirect the trace to a file?
Oh I got it. Strace doesn't print to stdout. It prints to stderr.
strace tmux 2> /tmp/blah works.
You can also use the -o option with strace which writes the trace output to the file rather than to stderr.
strace -o /tmp/blah tmux
Related
I have a screen instance running on remote machine. I want to execute commands on that screen like this:
ssh serverIp screen -S remote -p 0 -X stuff \"./build.sh^M\"
rsync -arvcL serverIp:/path/to/build.log build.log
The build.sh script invokes some make commands on the remote and saves it's output (using tee) to some file (let's call it build.log). Then I want to download build.log to my local machine.
How do I wait for the ./buils.sh to finish on remote, so I can download complete build.log?
You could wait for a file, created after your build script finished.
Something like
start-build.sh
#!/bin/bash
./build.sh
touch build.done
Then the command looks like:
ssh server 'rm -f build.done; screen -S remote -X stuff "./start-build^M"; while [ ! -f build.done ]; do sleep 1; done'
First it removes an old build.done file, then start the build inside the screen.
And then wait (outside of the screen) for the file build.done to exist.
Sometimes I get errors when I download files from a cloud with python-swiftclient, like this one:
Error downloading object 'uploads/1/image.png': Object GET failed: https://orbit.brightbox.com/v1/acc-12345/uploads/1/image.png 500 Internal Error b'An error occurred'
To search for the all errors and re-download failed files I would want to save output of the swift command to a file
I tried to do the following ways:
swift-cli -A https://orbit.brightbox.com/v1/acc-12345 \
-U user -K secret download uploads 2>&1 | tee uploads.log
# and
swift-cli -A https://orbit.brightbox.com/v1/acc-12345 \
-U user -K secret download uploads > uploads.log
But this didn't work. man swift describes -o option
For a single object download, you may use the -o [--output]
option to redirect the output to a specific file or if "-" then just redirect to stdout or with --no-download actually not to write anything to disk.
but when I try to download a directory with -o option if fails with
-o option only allowed for single file downloads
How can I save log to a file when I download a directory with swift CLI?
Actually redirecting output to a file works with swift-client:
swift-cli -A https://orbit.brightbox.com/v1/acc-12345 \
-U user -K secret download uploads > uploads.log
I was confused because after I started the command above, in another terminal window I did
tail -f uploads.log
But it didn't give me any output (like I was seeing when I was running the download command without redirection).
Seems like that swift-client writes to a file in batches and I needed to wait about a minute until tail -f dumps into the console a hundred of lines like this
uploads/documents/1/image.png [auth 0.000s, headers 0.390s, total 14.361s, 0.034 MB/s]
Httpd processes use a non-default configuration file if they are run with the -f flag.
For example
/home/myuser/apache/httpd-2.4.8/bin/httpd -f /confFiles/apache/2.4.8/apache.conf -k start
will use this configuration file: /confFiles/apache/2.4.8/apache.conf
I need to get this location and would rather not have to check for possible -f flags used to start httpd.
The answer here says to run /path/to/httpd -V and concatenate
-D SERVER_CONFIG_FILE="conf/httpd.conf"
with
-D HTTPD_ROOT="/etc/httpd"
to get the final path to the config file.
However, this path will not be the correct one if the -f flag is used to start the httpd process.
Is there a command that can get the config file that is actually being used by the process?
The answer you refer to mentions the paths httpd was compiled with, but as you say those can be manually changed with parameters.
The simple way to check is the command line, if process is called "httpd" (standard name), a simple ps will reveal the config file being used:
ps auxw | grep httpd
Or querying the server if server has mod_info loaded, in command line or with your favourite browser:
curl "http://yourserver.example.com/server-info?server" | grep -i "config file"
Note: mod_info should not be publicaly available for everyone to see.
I am trying to run a script in AIX to execute another script on a remote server. In addition to the remote script i need to send the stdout to /dev/null. The same command works fine on another server but when I run on the current server it hangs, any advice?
su - test -c "rsh testserver /scripts/testme" 2>&1 >/dev/null1
In your comment you write that a menu is presented when the user logins.
Let's say this is done in the .profile file, using echoes and a read command.
When a menu is presented, the read command in the menu code will not be skipped by redirecting the output. The menu still waits for your input and the su command seems to hang.
Can you change your .profile or .bashrc so that it will skip presenting the menu when called using a su command? When this is called during startup, you can look at the returncode of tty. When you use the su command from the commandline, you should look for another solution.
When your root shell is ksh, you can try the following:
if [[ "$(ps -fp $$)" != *"-ksh -c "* ]]; then
echo "Now I should call the Menu"
fi
I'm specifically looking for a solution for PuTTY but also interested for other terminal emulators, like Gnome Terminal.
My thought is it would be useful if I start a tar zxvf to be able to set a trigger on the terminal emulator, minimize it, and on next output to stdout/stderr I get a notification in the task bar that the command has finished.
This works for me:
echo -e "\a"
Then update your PuTTY session to use the Visual Bell, and set "Taskbar/caption indication on bell" to Flashing or Steady.
Then run this command after your tar completes:
tar xvzf file ; echo -e "\a"
Here is a screenshot: Save these settings as the default settings and/or the sessions' settings you have