With the open command in Perl, you can use a filehandle. However I have trouble getting back the exit code with the open command in Perl. With the system command in Perl, I can get back the exit code of the program I'm running. However I want to just redirect the STDOUT to some filehandle (no stderr). My stdout is going to be a line-by...
I have the following code, which I'm trying to only allow a maximum of 5 children to run at a time, but I can't figure out how to decrement the child count when a child exits. struct { char *s1; char *s2; } s[] = { {"one", "oneB"}, {"two", "twoB"}, {"three", "thr4eeB"}, {"asdf", "3th43reeB"}, {"asdfasdf", "thr33eeB"}, ...
I want to run program as daemon in remote machine in Unix. I have rsh connection and I want the program to be running after disconnection. Suppose I have two programs: util.cpp and forker.cpp. util.cpp is some utility, for our purpose let it be just infinite root. util.cpp int main() { while (true) {}; return 0; } forker.cp...
What's the fastest, best way on modern Linux of achieving the same effect as a fork-execve combo from a large process ? My problem is that the process forking is ~500MByte big, and a simple benchmarking test achieves only about 50 forks/s from the process (c.f ~1600 forks/s from a minimally sized process) which is too slow for the inten...
On an embedded platform (with no swap partition), I have an application whose main process occupies most of the available physical memory. The problem is that I want to launch an external shell script from my application, but using fork() requires that there be enough memory for 2x my original process before the child process (which wil...
This code works well in Mac/Linux, but not in Windows. import mmap import os map = mmap.mmap(-1, 13) map.write("Hello world!") pid = os.fork() if pid == 0: # In a child process print 'child' map.seek(0) print map.readline() map.close() else: print 'parent' What's the equivalent function of os.fork() on Window...
I have a Linux daemon that forks a few children and monitors them for crashes (restarting as needed). It will be great if the parent could monitor the memory usage of child processes - to detect memory leaks and restart child processes when the go beyond a certain size. How can I do this? ...
Hi , I have many directories and need to delete them periodically with minimum time. Additionally for each directories delete status need to know i.e whether deleted successfully or not. I need to write on the ksh . Could you please help me out. The sample code which I am using, in which I tried launching rm-rf in the background, is no...
In the code below I have a function int GetTempString(char Query[]); calling it in main works fine. However, when calling the function from a fork the fork hangs (stops running, no errors, no output) before this line: pch = strtok (Query," ,"); the printf shows that the pointer to pch is null. Again this only happens when the fork is ex...
I have forked an SVN project using Git because I needed to add features that they didn't want. But at the same time, I wanted to be able to continue pulling in features or fixes that they added to the upstream version down into my fork (where they don't conflict). So, I have my Git project with the following branches: master - the br...
I'm trying to find a good and simple method to signal child processes (created through SocketServer with ForkingMixIn) from the parent process. While Unix signals could be used, I want to avoid them since only children who are interested should receive the signal, and it would be overkill and complicated to require some kind of registra...
I'm currently writing an IRC bot. The scripts are loaded as perl modules in ZNC but the bot gets disconnected with an Input/Output error if I create a forked process. This is a working example script without fork, but this causes the bot to freeze until the script finishes doing its task. package imdb; use warnings; use strict; sub n...
Newbie question: On Unix, in a program with a parent and some children: - How can the parent alert the children efficiently to do some work.. ? - Or how can the children wait for parent signal to start doing some work? EDIT: This program tries to do a complex computation in parallel, I have already used shared memory as a common works...
If I fork a child process, and the child process exits before the parent calls waitpid, then is the exit status information that is set by waitpid still valid? If so, when does it become not valid; i.e., how do I ensure that I can call waitpid on the child pid and continue to get valid exit status information after an arbitrary amount o...
Hi every one ! I have a little problem. I have to code a simple C application that creat a process and his child (fork()) and I have to do an operation. Parent initialize the values and child calculate. I write this : #include <stdlib.h> #include <signal.h> #include <fcntl.h> #include <stdio.h> #include <unistd.h> typedef struct { ...
I'd like to use the namespacing features of the clone function. Reading the manpage, it seems like clone has lots of intricate details I need to worry about. Is there an equivalent clone invocation to good ol' fork()? I'm already familiar with fork, and believe that if I have a starting point in clone, I can add flags and options from ...
I'm honestly not clear on the semantics here. They're all about copies/variants of a code+history unit, but past that I'm not sure I could say. Is this logical structure explained somewhere? ...
I want to make a simple program, that fork, and the child writes into the named pipe and the parent reads and displays from the named pipe. The problem is that it enters the parent, does the first printf and then it gets weird, it doesn't do anything else, does not get to the second printf, it just ways for input in the console. #includ...
Hi, I have process A wich forks process B. A and B - are different application. Both compiled with -g flag. to run it with callgrind I use command: valgrind --tool=callgrind --trace-children=yes ./A [params] callgrind.out.xxx for parent process (A) contains function names. for child process(B) - it doesn't contains. What could be wron...
Throwing an exception via croak in a forked child process seems to print the error as a background process would. That is, it clobbers the shell prompt. If I die instead of croak, the the error message pops up as a foreground process. I've trying to find out why that is in the Carp documentation without any luck. Here's what I mean. Th...