My application running on embedded linux (busybox) tries to execute a script via popen(cmd, “r”). cmd = “sh /tmp/DF1_05/update.sh DF1_05” I can execute this script without problem launching it by hand from sh, but it fails when it’s launched by the application. The first lines of update.sh script are: I cannot even see the echo ouput. My application’s code is:
Tag: popen
Why is the following shell command working when executed directly in command line, but not working when executed through C program using popen/system?
The command is : ps -c -p | tr -s ” ” | cut -d ” ” -f 2,6-10,13 | grep ‘R’ I am running it through adb shell. Basically, I want a list of processes (and certain parameters) which are currently in the run queue. This is working fine if I run it directly through the shell. However, if
How can I execute two commands in terminal using Python’s subprocess module?
How can I use the subprocess module (i.e. call, check_call and Popen) to run more than one command? For instance, lets say I wanted to execute the ls command twice in quick sucession, the following syntax does not work returns: Answer You can use && or ;: The difference is that in case of && the second command will be
Wait for popen script to terminate in C
Is that possible with C to wait until the popen subprocess is finished? I have a script launched by a C daemon which will connect to a wifi network when an external signal is triggered. Here is my code for now : However, I’m not waiting for the subprocess to finish so when I’m closing the pipe, the ressource is
Get the status of a python process that was executed in another terminal
I have a python program that will create and execute another python script in a new terminal. To do so, I’m using subprocess.Popen. I’m trying to get the PID of the new process using .pid. However, the value of this pid doesn’t seem to match the real pid of the newly created process (the two values don’t match). Here’s a
Trying in PHP to mysqldump -v to popen and not getting output
I’m writing a wrapper for mysqldump and want to show the output nicely in a PHP CLI application. I’m attempting to run mysqldump -v using popen so that I can get the verbose output and display progress indicators to the user. However no output is returned (by default it gets logged to the screen via stdErr). I tried adding 2>&1
How to get the returned stdout of a program called with QProcess?
I am writing a program in Qt and currently using popen to run a linux command and read the output into a string: So I’d like to throw the above code away as I’d prefer to use higher level facilities provided by Qt if possible. Does anyone have an example of how to do this with QProcess or atleast a
Sending an arrow key with fprintf
I’m testing out pipes and have hit a little road block. I want to be able to simulate pressing the right arrow key through a file pointer opened by popen. The file pointer opens a display program on a different terminal, much like a projector. I would like to send a signal to advance the next image (the right arrow
Python 3.4.3 subprocess.Popen get output of command without piping?
I am trying to assign the output of a command to a variable without the command thinking that it is being piped. The reason for this is that the command in question gives unformatted text as output if it is being piped, but it gives color formatted text if it is being run from the terminal. I need to get
popen (“tar xvf tarball.tar”) works in debug but not release builds
I’m working on a C++ program for Ubuntu that downloads a tar archive using curl_easy_perform, and after the archive is downloaded into /tmp I use popen to execute the appropriate tar command line. When I run my program’s debug build then popen(“tar xvf /tmp/example.tar -C /tmp/existingdir”) works, but when I run this command in release builds the popen call always