02-26-2011
Quote:
Originally Posted by
tomlee
Thanks for your reply. But I want the child process can run in background, not in foreground
It is in the background, independent. Your program only wait()'s because you tell it to.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
how to write shell program. EX : to check whether a string is a palindrome or not. (9 Replies)
Discussion started by: raram
9 Replies
2. Shell Programming and Scripting
. I wrote shell script with help to extract data and generate report . I need help to modify that in sub section .
Currently I am generating the report in this format
Version Name Host Total Number of Fails
10 Animator 45
10 Krachel ... (0 Replies)
Discussion started by: getdpg
0 Replies
3. Shell Programming and Scripting
Hi Guys,
I need to write a shell script, to which I have getting results from CPU and Memory Utilization. This is to generate automatically through Shell script by running cron job. Is it possible to write it. I am new to this shell scripting.
Can you please help me on this ASAP.
... (6 Replies)
Discussion started by: lakshmanrk
6 Replies
4. Shell Programming and Scripting
I'm trying to read a bunch of log files and output the lines that contain particular strings.
To accomplish this, I've been running the following from the command line:
find . -name "*" | xargs grep " " | grep " " > output.txt
Two grep statements are needed in case I'm looking for a... (3 Replies)
Discussion started by: Rally_Point
3 Replies
5. IP Networking
Hi,
We have smb client running on two of the linux boxes and smb server on another linux system. During a backup operation which uses smb, read of a file was allowed while write to the same file was going on.Also simultaneous writes to the same file were allowed.Following are the settings in the... (1 Reply)
Discussion started by: swatidas11
1 Replies
6. Shell Programming and Scripting
Hi ,
i need to write a script
like this
In 1.sh
./test.sh
wait(5sec)
send ctrl+C to server
./testxxxx.sh
first i need invoke test.sh from 1.sh , after wating for some time i need to close the test.sh script & i need to start new script
i tried to invoke script... (2 Replies)
Discussion started by: pvr_satya
2 Replies
7. Shell Programming and Scripting
Hi, I need some help to write a script
i need to write script that will count the no of logs generated for the day and specify the logfiles names which is not generated for the day.
Default no of log generate per day is 29
if less than 29 logs generated it should specify the perticular logfile... (7 Replies)
Discussion started by: mail.chiranjit
7 Replies
8. UNIX for Dummies Questions & Answers
Dear Unix gurus,
We have a config shell script file which has 30 variables which needs to be passed to master unix shell script that invokes oracle database sessions. So those 30 variables need to go through the database sessions (They are inputs) via a shell script. one of the variable name... (1 Reply)
Discussion started by: dba1981
1 Replies
9. Shell Programming and Scripting
Dear Unix gurus,
We have a config shell script file which has 30 variables which needs to be passed to master unix shell script that invokes oracle database sessions. So those 30 variables need to go through the database sessions (They are inputs) via a shell script. one of the variable name... (1 Reply)
Discussion started by: dba1981
1 Replies
10. Shell Programming and Scripting
Please help me to write the shell script
AC|NAME|STATE|MAXVALUE|MINVALUE---------heading
111|UMA|ODISHA|123,00.00|54.00
111|UMA|ODISHA|124,00.00|25.00
111|UMA|ODISHA|114,00.00|58.00
111|UMA|ODISHA|104,00.00|00.00
111|UMA|ODISHA|194,00.00|19.00
111|UMA|ODISHA|184,00.00|64.00... (5 Replies)
Discussion started by: alokjyotibal
5 Replies
LEARN ABOUT CENTOS
tcl_reapdetachedprocs
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
Tcl Tcl_DetachPids(3)