Hi all,
i just started started learning system programming and want to pursue a career in the sys prog area.
below is the program that use a fork() call.
i read in one of the tutorials that parent process and child process uses different address spaces and runs concurrently.
that meas each process gets some slice of cpu time, then the statements in that process are executed.
my Questions:
1.is there any way to know how much timeslice each process is getting.
2.what kind of scheduling its using
3. can i print the out put one page at a time ( should wait for keypress to print next page)
4. any links that provides good system programming info(message queues, pipes,shared memory etc.. )
5. appications that uses sockets
6. fork returns zero to the child process and some +ve value to parent.
how is it able to return two values.
below is some example prog:
Code:
#include <stdio.h>
#include <sys/types.h>
#define MAX_COUNT 200
void ChildProcess(pid_t); /* child process prototype */
void ParentProcess(pid_t); /* parent process prototype */
void main(void)
{
pid_t pid;
pid = fork();
if (pid == 0)
ChildProcess(pid);
else
ParentProcess(pid);
}
void ChildProcess(pid_t pid)
{
int i;
char buf[40];
for(i=1; i <= MAX_COUNT; i++) {
sprintf(buf, "This line is from pid %d, value = %d\n", pid, i);
write(1, buf, strlen(buf));
}
}
void ParentProcess(pid_t pid)
{
int i;
char buf[40];
for(i=1; i <= MAX_COUNT; i++) {
sprintf(buf, "This line is from pid %d, value = %d\n", pid, i);
write(1, buf, strlen(buf));
}
}
I have a question regarding the recv syscall.
Suppose I have a client/server and the following exchange of message took place:
Client --> Server using multiple send syscalls one after another immediately:
send "Packet1"
send "Packet2"
send "Packet3"
Server receives in the... (2 Replies)
Hi all,
I am using ptrace to keep track of clone syscalls in a program. However, I found that the traced syscall cant be paired. for example, there are some syscalls that have entry, but without exit showing up in the traced sequences. So, is there anyway to distinguish the entry and exit of a... (0 Replies)
I saw somewhere that describe read() as a primitive. But when I lean signals, it says the read() may be interrupted by a signal.
My Question:
1, What is the diffence between primitive and reentrant?
2, Is read() a primitive or reentrant?
3, Are all system calls primitive or reentrant? (2 Replies)
Hello Experts,
If a Solaris process is calling some syscall, and right now execution is inside syscall doing only CPU work, for example the inside simplest times syscall,
-> app_func
=> times
<< we are here now, we have entered in the times, but not exited yet
<= times
<- app_func... (9 Replies)
hi!:)
i got a problem....:wall::wall:
i got several disks in my diskarray. I attached new disk to allocate it to the swap space.
The problem is : how to recognise the newly attached disk?
I've one more requirement -:wall:- i want to run dns service on another port number.how can i do... (2 Replies)
Hi,
I wanna add my own system call to Fedora 18 kernel 3.8.2.
From kernel 3.3 I heard there is a new system to add system calls.
So where i can find a guides ?
I wanna print this text: "Hello world!" in terminal, not dmesg. (4 Replies)
Hello to all
I want download a file in osx intel 64 with NASM , I want to use socket syscall
This is part of my code
section .data
command db "GET /test/2.gif HTTP/1.1\r\nHost: 10.1.1.187\r\n\r\n", 0
; url db "http://172.16.207.153/test/2.gif", 0
global main... (1 Reply)
Oflate we are finding a few servers experiencing severe slowness. What would be the commands that I need to try to postmortem the situation? (3 Replies)
Discussion started by: ggayathri
3 Replies
LEARN ABOUT SUNOS
getpid
getpid(2) System Calls getpid(2)NAME
getpid, getpgrp, getppid, getpgid - get process, process group, and parent process IDs
SYNOPSIS
#include <unistd.h>
pid_t getpid(void);
pid_t getpgrp(void);
pid_t getppid(void);
pid_t getpgid(pid_t pid);
DESCRIPTION
The getpid() function returns the process ID of the calling process.
The getpgrp() function returns the process group ID of the calling process.
The getppid() function returns the parent process ID of the calling process.
The getpgid() function returns the process group ID of the process whose process ID is equal to pid, or the process group ID of the calling
process, if pid is equal to 0.
RETURN VALUES
Upon successful completion, these functions return the process group ID. Otherwise, getpgid() returns (pid_t)-1 and sets errno to indicate
the error.
ERRORS
The getpgid() function will fail if:
EPERM The process whose process ID is equal to pid is not in the same session as the calling process, and the implementation
does not allow access to the process group ID of that process from the calling process.
ESRCH There is no process with a process ID equal to pid.
The getpgid() function may fail if:
EINVAL The value of the pid argument is invalid.
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), fork(2), getsid(2), setpgid(2), setpgrp(2), setsid(2), signal(3C), attributes(5), standards(5)SunOS 5.10 28 Dec 1996 getpid(2)
11-06-2009
