10 More Discussions You Might Find Interesting
1. Ubuntu
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
2. Shell Programming and Scripting
When command is executed by forking, the console displays the status of that command. I want to suppress it.. how to do it ?
Example:
var1=`date` &
echo "hello world";
output:
hello world
+ Done var1=`date`
I want to suppress the second line "+ Done var1=`date`".
I... (10 Replies)
Discussion started by: Arun_Linux
10 Replies
3. UNIX for Advanced & Expert Users
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)
Discussion started by: badsha6642
3 Replies
4. Programming
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)
Discussion started by: pnirmala
3 Replies
5. Shell Programming and Scripting
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)
Discussion started by: pnirmala
0 Replies
6. Homework & Coursework Questions
Use and complete the template provided. The entire template must be completed. If you don't, your post may be deleted!
1. The problem statement, all variables and given/known data:
i have a problem in understanding the behaviour of fork .
i understood fork as to create a new process and... (4 Replies)
Discussion started by: MrUser
4 Replies
7. UNIX for Dummies Questions & Answers
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)
Discussion started by: u_peerless
1 Replies
8. UNIX for Dummies Questions & Answers
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)
Discussion started by: arunviswanath
1 Replies
9. Programming
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)
Discussion started by: davidoff
2 Replies
10. UNIX for Advanced & Expert Users
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)
Discussion started by: kkumar1975
4 Replies
FORK(2) System Calls Manual FORK(2)
NAME
fork - spawn new process
SYNOPSIS
fork( )
DESCRIPTION
Fork is the only way new processes are created. The new process's core image is a copy of that of the caller of fork. The only distinc-
tion is the fact that the value returned in the old (parent) process contains the process ID of the new (child) process, while the value
returned in the child is 0. Process ID's range from 1 to 30,000. This process ID is used by wait(2).
Files open before the fork are shared, and have a common read-write pointer. In particular, this is the way that standard input and output
files are passed and also how pipes are set up.
SEE ALSO
wait(2), exec(2)
DIAGNOSTICS
Returns -1 and fails to create a process if: there is inadequate swap space, the user is not super-user and has too many processes, or the
system's process table is full. Only the super-user can take the last process-table slot.
ASSEMBLER
(fork = 2.)
sys fork
(new process return)
(old process return, new process ID in r0)
The return locations in the old and new process differ by one word. The C-bit is set in the old process if a new process could not be cre-
ated.
FORK(2)