I had put wait in parent ....so that parent will not terminate untill child will not free its resources........If I will not use wait in parent, the parent will terminate and child will be running.........
Yes that's fine, but it's not going to be waiting for input in select if it's blocking in wait4.
1. If I use an software application(which connects to the database in the server) in my local pc, how many PID should be registered? Would there be PID for the session and another PID for socket connection?
2. I noticed (through netstat) that when I logged in using the my software application,... (1 Reply)
Hello,
I need help to replace the ................. of client.c that request the server implemented by server.c
------------------
Listing 1 - server.c
/* Inclusion des différentes librairies nécessaires */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
... (0 Replies)
Sorry if this is a stupid question!
I have been developing a Java application that I am deploying on both Unix and Linux servers, which uses lots of socket handling. When the server side connection is dropped by the server un-gracefully I have been seeing close_waits and null connections.
... (0 Replies)
I have a socket and a message queue over which i am trying to multiplex input using select().
When data comes over socket the select works but when it comes over message queue the select is not detecting it .
Create_Q gets the identifier of the messege queue.
... (1 Reply)
Hi,
I was porting ipv4 application to ipv6; i was done with TCP transports. Now i am facing problem with SCTp transport at runtime.
To test SCTP transport I am using following server and client socket programs. Server program runs fine, but client program fails giving Invalid Arguments for... (0 Replies)
Hi all,
On the server side, one socket is used for listening, the others are used for communicating with the client.
My question is: if i want to set option for socket, which socket should be set on?
If either can be set, what's the different?
Again, what's the different if set option... (1 Reply)
Why does this socket function only read the first 1440 chars of the stream. Why not the whole stream ? I checked it with gdm and valgrind and everything seems correct...
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include... (3 Replies)
Dear Experts,
i am compiling my code in suse 4.1 which is compiling fine,
but at runtime it is showing me for socket programming error no 88
as i searched in errno.h it is telling me socket operation on non socket,
what is the meaning of this , how to deal with this error , please... (1 Reply)
I need clarification on whether it is okay to set socket options on a listening socket
simultaneously when it is being used in an accept() call?
Following is the scenario:-
-- Task 1 - is executing in a loop - polling a listen socket, lets call it 'fd', (whose file descriptor is global)... (2 Replies)
Hello, I'm stuck and this is a matter which I need to resolve quite fast (but I couldn't post in the "Emergency" section); the problem is this :
I have created a chat program in which the client sends the sentence to the server and then the server should send it to all the clients connected,... (2 Replies)
Discussion started by: timmyyyyy
2 Replies
LEARN ABOUT OPENSOLARIS
wait
wait(3C) Standard C Library Functions wait(3C)NAME
wait - wait for child process to stop or terminate
SYNOPSIS
#include <sys/types.h>
#include <sys/wait.h>
pid_t wait(int *stat_loc);
DESCRIPTION
The wait() function will suspend execution of the calling thread until status information for one of its terminated child processes is
available, or until delivery of a signal whose action is either to execute a signal-catching function or to terminate the process. If more
than one thread is suspended in wait(), waitpid(3C), or waitid(2) awaiting termination of the same process, exactly one thread will return
the process status at the time of the target process termination. If status information is available prior to the call to wait(), return
will be immediate.
If wait() returns because the status of a child process is available, it returns the process ID of the child process. If the calling
process specified a non-zero value for stat_loc, the status of the child process is stored in the location pointed to by stat_loc. That
status can be evaluated with the macros described on the wait.h(3HEAD) manual page.
In the following, status is the object pointed to by stat_loc:
o If the child process terminated due to an _exit() call, the low order 8 bits of status will be 0 and the high order 8 bits will
contain the low order 7 bits of the argument that the child process passed to _exit(); see exit(2).
o If the child process terminated due to a signal, the high order 8 bits of status will be 0 and the low order 7bits will contain
the number of the signal that caused the termination. In addition, if WCOREFLG is set, a "core image" will have been produced;
see signal.h(3HEAD) and wait.h(3HEAD).
One instance of a SIGCHLD signal is queued for each child process whose status has changed. If wait() returns because the status of a child
process is available, any pending SIGCHLD signal associated with the process ID of that child process is discarded. Any other pending
SIGCHLD signals remain pending.
If the calling process has SA_NOCLDWAIT set or has SIGCHLD set to SIG_IGN, and the process has no unwaited children that were transformed
into zombie processes, it will block until all of its children terminate, and wait() will fail and set errno to ECHILD.
If a parent process terminates without waiting for its child processes to terminate, the parent process ID of each child process is set to
1, with the initialization process inheriting the child processes; see Intro(2).
RETURN VALUES
When wait() returns due to a terminated child process, the process ID of the child is returned to the calling process. Otherwise, -1 is
returned and errno is set to indicate the error.
ERRORS
The wait() function will fail if:
ECHILD The calling process has no existing unwaited-for child processes.
EINTR The function was interrupted by a signal.
USAGE
Since wait() blocks on a stopped child, a calling process wanting to see the return results of such a call should use waitpid(3C) or
waitid(2) instead of wait(). The wait() function is implemented as a call to waitpid(-1, stat_loc, 0).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Interface Stability |Standard |
+-----------------------------+-----------------------------+
|MT-Level |Async-Signal-Safe |
+-----------------------------+-----------------------------+
SEE ALSO Intro(2), exec(2), exit(2), fork(2), pause(2), waitid(2), ptrace(3C), signal(3C), signal.h(3HEAD), waitpid(3C), wait.h(3HEAD),
attributes(5)SunOS 5.11 9 Jun 2004 wait(3C)