On Wednesday 08 December 2004 13:23, Noah yan wrote: > Hi, I am very new and have questions for the process control in Linux > or Unix? > > What is the difference between a STOPPED process(signalled by > SIGSTOP) and a sleeping process? I know I can continue a process by > signaling SIGCONT, how to wake up a process from user-level? A sleeping process is just waiting for some event to occur which will wake it up. e.g. keyboard input, disk I/O completed, signal, ... A stopped process will remain stopped (not runable) until it gets a continuation signal (e.g. SIGCONT). Very few process will ever be in a STOPPED state, but most will spend most of their time in a SLEEPING state. > Is there posibble to pass parameters to signal handler? maybe one > posibble way is to set a environment variable that can be catched by > the signal-handler? Is there other way to do that, like passing > arguments in function call? Well, the signal handlers _do_ take parameters, but I suspect that isn't what you are looking for. See the sa_handler and sa_sigaction members of the struct sigaction. -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
