hi there, im trying to produce this program that would run at first, and when it runs it will fork one child process to [exec] a program and then another forking to run this other program, and then another one .
i cant seem to get it right can someone help me please here is what is got so far:
hi experts(novice people can stay away as it is no child's game),
i am developing a script which works like recycle bin of windows.
the problem i am facing is that when ever i am trying to delete a file which is situated in parent directory or parent's parent directory i am unable to... (1 Reply)
Hi, as I understand fork(), it makes a copy of the parent which becomes a child. But is there anyway to make three children for that one parent. So in other words, if I look up the getppid() of the children, I want them to have the same value??
Thanks in advance to any help! (1 Reply)
I want take a flash backup by flar command for specific files like:
/ , /boot, /tmp
I am trying this command but its not working
# flar -n archive1 -f /,/boot,/tmp -F -c /home/arc1.flar
Please can any body help me __.____._ (2 Replies)
Hello friends,
I have compiled the kernel .
But now i am facing the problem as to how we can create the initrd.img for the specific kernel.
I was compiling the 2.6.29 kernel.
to create initrd.img for 2.6.29
what i did is :
cd /boot
mkinitramfs-kpkg -o initrd.img-2.6.29 2.6.29... (2 Replies)
Hi Everyone,
Please refer to attached test.zip.
Open a.htm, tested under IE, Safari, Firefox no problem, but ONLY google chrome fail, seems cannot use call parent javascript function under the child iframe.
Please advice.
Thanks (1 Reply)
Write a program using select, which will create some number of child processes that continuously send text messages to the parent process using pipes. Each child has its own pipe that it uses to communicate with the parent. The parent uses select () to decide what pipes should be processed to... (1 Reply)
The task I have to do is something along the lines "I receive some input and based on the first character I send it through pipe to one of the children to print".
The scheme it is based on is 1->2; 1->3; 1->4; 2 will print all the input that starts with a letter, 3 will print all the input that... (2 Replies)
Discussion started by: Ildiko
2 Replies
LEARN ABOUT ULTRIX
fork
fork(2) System Calls Manual fork(2)Name
fork - create a new process
Syntax
#include <sys/types.h>
#include <unistd.h>
pid = fork()
pid_t pid;
Description
The system call causes creation of a new process. The new process (child process) is an exact copy of the calling process except for the
following:
o The child process has a unique process ID.
o The child process has a different parent process ID (that is, the process ID of the parent process).
o The child process has its own copy of the parent's descriptors. These descriptors reference the same underlying objects, so that, for
instance, file pointers in file objects are shared between the child and the parent, so that a on a descriptor in the child process
can affect a subsequent read or write by the parent. This descriptor copying is also used by the shell to establish standard input
and output for newly created processes as well as to set up pipes.
o The child processes resource utilizations are set to 0. For further information, see
Return Values
Upon successful completion, returns a value of 0 to the child process and returns the process ID of the child process to the parent
process. Otherwise, a value of -1 is returned to the parent process, no child process is created, and the global variable errno is set to
indicate the error.
Diagnostics
The system call fails and no child process are created under the following conditions:
[EAGAIN] The system-imposed limit {PROC_MAX} on the total number of processes under execution would be exceeded.
[EAGAIN] The system-imposed limit {CHILD_MAX} on the total number of processes under execution by a single user would be exceeded.
[ENOMEM] There is insufficient swap space for the new process.
See Alsoexecve(2), wait(2)fork(2)