I desperately wanted one of the UNIX Gurus to help me resolve my problem asap(I have to deliver the code to the client by Monday 08-oct).
I have a file with around 5 million records (50 lakhs). Now my original process was taking around 30 hours to read the complete file, process each and every... (4 Replies)
One more question. How can i calculate the time that system needs to make fork() system call? I need to make it with times function but i really don't know how. :( (2 Replies)
Hi,
Ho do I differentiate system call from library call?
for example if I am using chmod , how do I find out if it is a system call or library call?
Thanks
Muru (2 Replies)
Can anyone explain me what really happens when a system call fork() is called ?
I like to know what happens internally.
Thanks in Advance.
- Arun (1 Reply)
Hi folks,
I want to know how this below program works?
#include <stdio.h>
int main()
{
printf("A\n");
fork();
printf("B\n");
fork();
fork();
printf("D\n");
fork();
printf("C\n");
}
This is just for example. How this type of programs where fork is used many places, how the... (1 Reply)
hi,
i tried the following source codes:
fork1.c:
main()
{
printf("demo of fork\n");
fork();
printf("hello");
}
output:
demo of fork
hello hello
fork2.c:
main()
{
printf("demo of fork"); (0 Replies)
hi all,
i tried the following source codes:
fork1.c:
main()
{
printf("demo of fork\n");
fork();
printf("hello");
}
output:
demo of fork
hello hello
fork2.c:
main() (3 Replies)
Hi
I wrote a simple fork program to illustrate the fork() system cal. here it is
#include<stdio.h>
#include<sys/stat.h>
#include<sys/types.h>
main()
{
int flag;
flag=fork();
if(flag==0)
{
printf("Child \n");
printf("Process id= %d\n",getpid());
... (3 Replies)
Hi, I'm writing a shell script where I want to call fork(). However I wrote like this "var=fork()" in c style and got this error:
"syntax error near unexpected token `(' "
How could I call fork() in shell script? Thanks in advance.
Duplicate Post - Continue Here - Please Do Not Cross Post... (0 Replies)
Hi, I'm writing a shell script where I want to call fork(). However I wrote like this "var=fork()" in c style and got this error:
"syntax error near unexpected token `(' "
How could I call fork() in shell script? Thanks in advance. (2 Replies)
Discussion started by: Xiaoya
2 Replies
LEARN ABOUT CENTOS
getppid
GETPID(2) Linux Programmer's Manual GETPID(2)NAME
getpid, getppid - get process identification
SYNOPSIS
#include <sys/types.h>
#include <unistd.h>
pid_t getpid(void);
pid_t getppid(void);
DESCRIPTION
getpid() returns the process ID of the calling process. (This is often used by routines that generate unique temporary filenames.)
getppid() returns the process ID of the parent of the calling process.
ERRORS
These functions are always successful.
CONFORMING TO
POSIX.1-2001, 4.3BSD, SVr4.
NOTES
Since glibc version 2.3.4, the glibc wrapper function for getpid() caches PIDs, so as to avoid additional system calls when a process calls
getpid() repeatedly. Normally this caching is invisible, but its correct operation relies on support in the wrapper functions for fork(2),
vfork(2), and clone(2): if an application bypasses the glibc wrappers for these system calls by using syscall(2), then a call to getpid()
in the child will return the wrong value (to be precise: it will return the PID of the parent process). See also clone(2) for discussion
of a case where getpid() may return the wrong value even when invoking clone(2) via the glibc wrapper function.
SEE ALSO clone(2), fork(2), kill(2), exec(3), mkstemp(3), tempnam(3), tmpfile(3), tmpnam(3), credentials(7)COLOPHON
This page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
Linux 2008-09-23 GETPID(2)