Hi,
I have a trap problem when calling a child script in the background.
I know there are a lot of threads here on the issue of traps and signals, I think I have read all the relevant ones, but still haven't found an answer to my problem.
I'm working on Linux or HP, the script as you can see... (4 Replies)
Hi,
I am using ksh to write my shell script. I need to create multiple-level of nested sub shells in my script. Lets say I have at n th subshell. My question is how do I come out from there to main login shell.
If I use 'exit' command then it is exiting from just one subshell and back to... (4 Replies)
Hi All,
I have two ksh script. 1st script calls the 2nd script and the second script calls an 'C' program.
I want 1st script to wait until the 'C' program completes.
I cant able to get the process id for the 'C' program (child process) to make the 1st script to wait for the second... (7 Replies)
Hey all, I need to launch a script from within 2 other scripts that can run independently of the two parent scripts... Im having a hard time doing this, if anyone knows how please let me know.
More detail.
ScriptA (bash), ScriptB (ksh), ScriptC (bash)
ScriptA, launches ScriptB
ScirptB,... (7 Replies)
hi,
I have a job that spawns multiple child processes in background.. Catch is i want to wait for some jobs to finish before i spawn more background processes. (each job creates a file and deletes at the end of it . so i don't want start new jobs after x amount of disk size is used up)
now,... (2 Replies)
Hello, everyone.
Here's a program:
pid_t pid = fork();
if (0 == pid) // child process
{
execvp ...;
}
I send a signal (such as SIGINT) to the parent process, the child process receive the signal as well as the parent process.
However I don't want to child process to receive the... (7 Replies)
Hi everyone
i am very new to linux , working on bash shell.
I am trying to solve the given problem
1. Create a process and then create children using fork
2. Check the Status of the application for successful running.
3. Kill all the process(threads) except parent and first child... (2 Replies)
Hello all; hope someone can help me cause I am going crazy trying to find a solution for (what I think is simple) issue...looked hard up and down this forum and tried several "solutions" with no avail...so here's my issue:
I have this (parent) script: copylsofdcmcadefttosftpwithmove.sh
... (3 Replies)
Hi,
I have parent script which is invoking multiple child scripts. I would want to kill all the child processes before the parent
process exit.
> cat ./parent
#!/bin/ksh
while
do
. ./child arg1 &
if ; then
break
fi
done
Is there a way to get the process group id for all the child... (3 Replies)
hi,
i want to call a child shell script from a parent shell script. the child will be running for 5 mins. normally when the child is running, parent will wait till the child completes. so in the above case parent will be paused for 5 mins. is there a way so that the parents does not wait for the... (3 Replies)
Discussion started by: Little
3 Replies
LEARN ABOUT MOJAVE
tcl_waitpid
Tcl_DetachPids(3) Tcl Library Procedures Tcl_DetachPids(3)__________________________________________________________________________________________________________________________________________________NAME
Tcl_DetachPids, Tcl_ReapDetachedProcs, Tcl_WaitPid - manage child processes in background
SYNOPSIS
#include <tcl.h>
Tcl_DetachPids(numPids, pidPtr)
Tcl_ReapDetachedProcs()
Tcl_Pid
Tcl_WaitPid(pid, statusPtr, options)
ARGUMENTS
int numPids (in) Number of process ids contained in the array pointed to by pidPtr.
int *pidPtr (in) Address of array containing numPids process ids.
Tcl_Pid pid (in) The id of the process (pipe) to wait for.
int *statusPtr (out) The result of waiting on a process (pipe). Either 0 or ECHILD.
int options (in) The options controlling the wait. WNOHANG specifies not to wait when checking the process.
_________________________________________________________________DESCRIPTION
Tcl_DetachPids and Tcl_ReapDetachedProcs provide a mechanism for managing subprocesses that are running in background. These procedures
are needed because the parent of a process must eventually invoke the waitpid kernel call (or one of a few other similar kernel calls) to
wait for the child to exit. Until the parent waits for the child, the child's state cannot be completely reclaimed by the system. If a
parent continually creates children and doesn't wait on them, the system's process table will eventually overflow, even if all the children
have exited.
Tcl_DetachPids may be called to ask Tcl to take responsibility for one or more processes whose process ids are contained in the pidPtr
array passed as argument. The caller presumably has started these processes running in background and does not want to have to deal with
them again.
Tcl_ReapDetachedProcs invokes the waitpid kernel call on each of the background processes so that its state can be cleaned up if it has
exited. If the process has not exited yet, Tcl_ReapDetachedProcs does not wait for it to exit; it will check again the next time it is
invoked. Tcl automatically calls Tcl_ReapDetachedProcs each time the exec command is executed, so in most cases it is not necessary for
any code outside of Tcl to invoke Tcl_ReapDetachedProcs. However, if you call Tcl_DetachPids in situations where the exec command may
never get executed, you may wish to call Tcl_ReapDetachedProcs from time to time so that background processes can be cleaned up.
Tcl_WaitPid is a thin wrapper around the facilities provided by the operating system to wait on the end of a spawned process and to check a
whether spawned process is still running. It is used by Tcl_ReapDetachedProcs and the channel system to portably access the operating sys-
tem.
KEYWORDS
background, child, detach, process, wait
TclTcl_DetachPids(3)