I find the stdout/stderr are great at tracking progeny processes:
When all processes that did not redirect both stdout and stderr exit, then stdin on cat goes to EOF and it exits.
These 3 Users Gave Thanks to DGPickett For This Post:
Have a need to schedule programs that can run after other programs are completed. Here's the catch:
1) The list of programs will not always be the same (kind of a plug-n-play deal)
2) The invoking shell may not be the same as the shell of the program being waited on
In other words, I need... (2 Replies)
As far as I can tell, the bash wait command waits for a logical "AND" of all the child processes.
Assuming I am coding in C:
(1) What is the function I would use to create multiple bash child process running perl?
(2) What is the function I would use to reinvent the bash wait command so I... (4 Replies)
Hi All
Here i have a piece of code,
set filename "./GopiRun.sh"
#I need to wait here until the GopiRun.sh is completed how do i achive this
exit. (1 Reply)
Hi
I have a shell script A which calls another 10 shell scripts which run in background. How do i make the parent script wait for the child scripts complete, or in other words, i must be able to do a grep of parent script to find out if the child scripts are still running.
My Code:
... (1 Reply)
I am trying to find a list of files and writing it to a text file. Based on the machine performance the file writing will be slow at certain time.
The code to find file and redirecting the output to text file is on a shell script
/usr/bin/find $SEARCH_DIR -daystart \( \( -name 'KI*' -a... (4 Replies)
Hello. I want to make a child do some stuff,wait,then the parent does some stuff and then child does some stuff and waits again.I have made the following but it does not work.Can anybody help me?
pid1 = fork();
if (pid1 == -1)
{
perror("Can't create child\n");
... (18 Replies)
I have the shell script to call a Perl routine and pass the Informatica WorkFlow name to it. Jobs in each group executes in background do not seem to wait at all. How do I make it to WAIT for the prior group to complete before execute the next group of jobs?
Sample of the jobs flow:
{
... (6 Replies)
Hey all,
I want to automate tarring a directory then using ftp to transfer the files over.
I was able to put the commands together but what I'm noticing is that only the very first file is being tarred and then transferred.
tar cvpf new.backup sourceAbove is the command I'm using which works... (4 Replies)
Hi all,
I am starting mgen5 for sometime depends on input from a file, in a child process. now I want to make parent to wait in this child process till mgen5 finishes, or timeout happens.
could anyone please tell me how to make parent to wait in child process in shell script?
thanks... (2 Replies)
Hi
I am facing a problem in my ksh.
My main script is calling 3 different child process in the background.
I am using wait to finish all and then submit another 3 child processes.
Now what i want is , whenever any one child process finishes ,i want to submit next one.so that parallel 3... (2 Replies)
Discussion started by: Sangu
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)