Assuming the process has made no significant changes to its arguments, environment variables, and file descriptors, it's not that hard to re-execute the exact same process.
As long as you can get the original arguments, anyway.
In general, with C/C++:
With Bourne shell:
There are some things to be aware of - a process that changes directory might make the arguments "wrong", and if a process is started with a different zeroth argument than the actual command/executable file name. For example, a login bash shell is usually started with the zeroth argument set to "-bash", even though the bash executable is usually something like /bin/bash. If you try to do "exec $0" from a bash login shell, it'll probably fail.
The problem in C/C++ is getting the original arguments if you're deep inside an executable. On Linux, you can probably find the original arguments in the global "__libc_argv" symbol. On Solaris, it's "___Argv". These are in libc.so on both operating systems, which is linked into just about every running process when it starts. (Linux binaries can still be statically linked, so beware if you're dealing with one of those.)
And in any case they have to be preserved. If something along the way modifies them, you can't recover them.
Hello all,
I would be happy if any one could help me with a shell script that would determine all the processes running on a Unix server and post a mail if any of the process is not running or aborted.
Thanks in advance
Regards,
pradeep kulkarni.
:mad: (13 Replies)
Hi Experts, we do have a shell script for Unix Solaris, which will kill all the process manullay, it used to work in my previous env, but now it is throwing this error.. could some one please help me to resolve it
This is how we execute the script (and this is the requirement) ... (2 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)
get email notification from from system when a process from XXXX user takes longer than 15 min run.Let me know the time estimation for the same.
hi ,any one please tell me , how to write a script to get email notification from system when a process from as mentioned above a xxxx user takes... (1 Reply)
Hi Experts,
I am facing one problem here which is one process always stuck in running state which causes the other similar process to sleep state . This causes my system in hanged state.
On doing cat /proc/<pid>wchan showing the "__init_begin" in the output.
Can you please help me here... (0 Replies)
Hi Experts,
I am facing one problem here which is one process always stuck in running state which causes the other similar process to sleep state . This causes my system in hanged state.
On doing cat /proc/<pid>wchan showing the "__init_begin" in the output.
Can you please help me here... (1 Reply)
Hi Experts,
I am facing one problem here which is one process always stuck in running state which causes the other similar process to sleep state . This causes my system in hanged state.
On doing cat /proc/<pid>wchan showing the "__init_begin" in the output.
Can you please help me here... (6 Replies)
I am writing a script to kick off a process to gather logs on multiple nodes in parallel using "&". These processes create individual log files. Which I would like to filter and convert in CSV format after they are complete. I am facing following issues:
1. Monitor all Processes parallelly.... (5 Replies)
Team,
I have multiple batchjobs running in VM, if I do ps -ef |grep java or tomcat I am getting multiple process list.
How do I get my exact tomcat process running and that is unique? via shell script? (4 Replies)
Discussion started by: Ghanshyam Ratho
4 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)