embedded-linux

问题 I need to SSH to an embedded device, launch a background program, then disconnect and keep the background process running. The problem is that the embedded device is using the ash shell (NOT bash or anything else), so nohup and screen are NOT available. I have not been able to find any way of disconnecting the process in ash. Is there any way of doing this in ash? 回答1: An alternative to: nohup command & Using clever parentheses: (( command & ) & ) And also if you want to drop stdin/stdout: ((

问题 I need to SSH to an embedded device, launch a background program, then disconnect and keep the background process running. The problem is that the embedded device is using the ash shell (NOT bash or anything else), so nohup and screen are NOT available. I have not been able to find any way of disconnecting the process in ash. Is there any way of doing this in ash? 回答1: An alternative to: nohup command & Using clever parentheses: (( command & ) & ) And also if you want to drop stdin/stdout: ((

问题 I need to SSH to an embedded device, launch a background program, then disconnect and keep the background process running. The problem is that the embedded device is using the ash shell (NOT bash or anything else), so nohup and screen are NOT available. I have not been able to find any way of disconnecting the process in ash. Is there any way of doing this in ash? 回答1: An alternative to: nohup command & Using clever parentheses: (( command & ) & ) And also if you want to drop stdin/stdout: ((

问题 I have an embedded system and want to use /dev/fb0 directly. As a first test, I use some code based on example-code found everywhere in the net and SO. Opening succeeds, also fstat and similar. But mmap fails with EINVAL. Source: #include <stdlib.h> #include <unistd.h> #include <stdio.h> #include <fcntl.h> #include <linux/fb.h> #include <sys/mman.h> #include <sys/ioctl.h> int main() { int fbfd = 0; struct fb_var_screeninfo vinfo; struct fb_fix_screeninfo finfo; long int screensize = 0; char

问题 I recently discovered Yocto. I'm able to successfully build an image using the command bitbake fsl-image-gui . But now, I would like to browse the code, the project specific code and the Kernel code for the fsl-image-gui but I cannot figure how ? Where is the source code when I build my Yocto project and how could I browse it ? 回答1: There are two halves of the Yocto setup: The sources/ directory, containing the bitbake recipes and supporting configuration, and The build/ directory, where the

问题 I am developing an application for embedded Linux (ARM). It will execute 500 times/sec, therefore speed is important. I would prefer to use C++ but I am afraid it will be slower than C even if I avoid fancy features like virtual functions. Is there a reason to use C or it's just as fine to write in C++? 回答1: C++ in general suffers no run time penalty over C - (except for a few things like RTTI). Except in a few odd circumstances the compiler should be able to determine which virtual function

问题 I am developing an application for embedded Linux (ARM). It will execute 500 times/sec, therefore speed is important. I would prefer to use C++ but I am afraid it will be slower than C even if I avoid fancy features like virtual functions. Is there a reason to use C or it's just as fine to write in C++? 回答1: C++ in general suffers no run time penalty over C - (except for a few things like RTTI). Except in a few odd circumstances the compiler should be able to determine which virtual function

问题 I want to test the mcheck functionality on my PC first to detect the malloc consolidate error. This way, i will be sure that this will help to figure out a similar crash on embedded-linux box. Unfortunately, the crash takes atleast 3-4 days. Thus, I am looking for a sample program that will generate the similar kind of crash as shown below. Program terminated with signal 6, Aborted. #0 0x2c73ebb8 in __syscall_kill (pid=900, sig=6) at kill.c:15 15 static inline _syscall2(int, __syscall_kill, _

问题 In general hardware interrupts need to be processed immediately, at least so as to acknowledge it and do some first level of processing. As I understand this is not scheduled activity. Please correct me. So the question is how to choose a processor that would actually execute this hardware interrupt handler? One can answer this for Linux and/or BSD systems 回答1: In general, this depends on the functionality offered by multi-core processor and OS. While using multi-core processors, you might

问题 i started with device driver for arm ... there i saw for each handler mention --- __attribute__((interrupt( irq ))) -.I am confused how this attribute will place a call to our driver routine ..?? IRQ of arm have following Vector address--- 0x00000018 (or 0xFFFF0018) As there can be many interrupt handler on same line. Suppose if we have 4 device driver each with its own IRQ to be reistered. Means some startup code will be provided by the GCC compiler for the IRQ handler & compiler will place