In my (concurrent)server programm,
I am handling accept problem from client like this.
sample of server code.
/*******************/
end = 0;
while (! end )
{
sockfd = accept(...)
if(sockfd == -1)
{
if (errno == EINTR) /* this is bcoz of SIGCHLD recvd from child
*/
{
continue;
}
else
/* display error and come out*/
{
end = 1;
}
}
else
{
/* continue further ...........*/
}
}
/*******************/
Is there any way to catch where the error is occuring in the client
process?
(like the line number / or suggest any debugging procedure)
end = 0;
while (! end )
{
sockfd = accept(...)
if(sockfd == -1)
{
if (errno == EINTR) /* this is bcoz of SIGCHLD recvd from child
*/
{
continue;
}
else
/* display error and come out*/
{
end = 1;
}
}
else
{
/* continue further ...........*/
}
}
i could not find the corresponding if to the else
the else with continue further...
yes ..
it is a sample part of my server code ..
if child gets killed abruptly then in my server (which is parent process)program, i am checking for EINTR.
but i wanted to check in detail where in my child process, this is happening.
Hi,
finally I got some reasonable trace by using truss command in AIX .
syntax is ..
truss -d -f -p -o jj_trc 5054664
where,
5054664 is the parent pid, on which i did the trace.
jj_trc is the output trace file
-f forces to trace on the childs
I also attached the trace file.
I am triying to find the cause..
Any body simultaneously also can check..
and this is how I handling the signal..
Code:
static void trtCHLD(int X)
{
int status ;
pid_t ret_pid;
fprintf( stderr, "*** SIGNAL SIGCHLD RECEIVED ***\n");
while ((ret_pid = waitpid((pid_t) -1,(int *) &status ,WNOHANG | WUNTRACED)) > 0);
if (ret_pid > 0)
{
if (WIFEXITED(status)) {
fprintf(stderr, "Child exited with RC=%d\n", WEXITSTATUS(status));
}
if (WIFSIGNALED(status)) {
fprintf(stderr, "Child exited via signal %d\n", WTERMSIG(status));
}
}
signal(SIGCHLD,trtCHLD);
return;
}
and calling this fn in the server..
Code:
signal(SIGCHLD,trtCHLD);
before the accept call..
but in the traces files I am not finding any messages getting printed as used in the file.
Is there any changes reqd for the arguements to waitpid function?
Pl any body can have a look at the trace file (generated using truss command) attached in my prev. posting and suggest me on this...
In my (concurrent)server programm,
I am handling accept problem from client like this.
sample of server code.
/*******************/
end = 0;
while (! end )
{
sockfd = accept(...)
if(sockfd == -1)
{
if (errno == EINTR) /* this is bcoz of SIGCHLD recvd from child
*/
{
continue;
}
else
/* display error and come out*/
{
end = 1;
}
iavpbmwtvdo
I'm testing out how to use SIGCHLD and I had a question about intercepting the signal and executing an action in the signal handler.
signal(SIGCHLD,countdown);
What I'm trying to achieve is be able to printf(Hello) every second that child is set to sleep.
I'm setting sleep = 3;
so... (1 Reply)
Hi. I have a program whose job it is to manage 15 child processes. Sometimes these children die (sometimes deliberately other times with a SEGV). This causes a SIGCHLD to be sent to my program which uses waitpid() in the signal handler to gather information and, in most cases, restart the child.... (3 Replies)
Hi all, this warning is driving me nuts. I use -pedantic with -Wall and -Werror so this needs to be fixed.
BUILD: GNU-Linux-x86
Any ideas?
struct sockaddr_in server_addr;
int addr_len = sizeof (server_addr);
fd = accept(link->socket_fd,
(struct sockaddr_in *)... (2 Replies)
Hello,
I'd like to know whether it is possible to let the parent know who kills its child process. The case is likely as below:
if there are four processes, we call them A, B, C and D. B is the child of A, and can be killed by both C and D. if B is killed, then A will receive SIGCHLD from B.... (7 Replies)
Hi
I am facing the problem where my HP Unix system date is in accordance with the current date but the logs written by the same is of previous time stamp.
Eg. System Date - Thu Mar 15 18:00:04 IST 2007
Syslogs -
Mar 15 12:30:10 mac@1 ftpd: FTP LOGIN FROM xx.xxx.xxx.xx , main
The ftp... (1 Reply)
Hi,
I have 2 processes X and Y. Y is exec() from X. In Y i have an exit handler, which is called when i return from main. With in exit handler i delete and object which in turn calls the destructor of the object, which terminates all the threads of Y.
I believe that SIGCHLD is raised by Y as... (4 Replies)
Hi,
I have an c++ application which uses the function fork and execvp().
The parent does not wait until the child ends. The parents just creates children and let them do their stuff.
You can see the parent program as a batch-manager.
I have added a SIGCHLD handler to the program:
void... (3 Replies)
Hello everybody, this is my first post on this forum. I have a program that has a child process that sleeps for 5 second and exit. I'm suppose to modify this program so that when the child exits, the parent reports the exit status of the child, so I also have to deal with SIGINT and SIGQUIT. Can... (1 Reply)
adv reqd on SIGCHLD on accept call
