10 More Discussions You Might Find Interesting
1. UNIX for Dummies Questions & Answers
Hello everyone,
I am a complete newbie to UNIX. I am using Debian LXDE 64-bit. I have a question regarding the child and parent process communication. According to wikipedia.org and various other sources, when a child process exits it sends the SIGCHLD signal to its parent... (1 Reply)
Discussion started by: sreyan32
1 Replies
2. Shell Programming and Scripting
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)
Discussion started by: vizz_k
2 Replies
3. Programming
This needs to work on HPUX and Linux.
I do a fork and create a child process. During execution of the child process, it is possible child become lost or get killed. That is the reason why I create the child process. However if the child process doesnt get killed, I do want to know the return... (2 Replies)
Discussion started by: usustarr
2 Replies
4. UNIX Desktop Questions & Answers
below is my code , but for some reason the return part is not working, only file transfer is happening and no exit status is checked .please me help me to fix this code
#!/bin/sh
#set -vx
ftp -nv sitelocation << !
user username password
lcd localdir
cd /remote dir
mget *.*
... (4 Replies)
Discussion started by: gwrm
4 Replies
5. UNIX for Advanced & Expert Users
Hi,
I have an application where if it runs indivisually could able to execute commands (like system("ls")) and could able to execute tcl script.
Same application if started from health monitor process (From health monitor process my application will be forked), it could not execute the... (1 Reply)
Discussion started by: chandrutiptur
1 Replies
6. UNIX for Dummies Questions & Answers
Hi All,
I have a problem to identify the error code thrown by FTP Server while uploading files.
The message is : ftp return 32.
I couldn't find out what is the meaning of that. :confused:
OS is Sun Solaris 2.10.
Anyone can help?
Thanks a lot (1 Reply)
Discussion started by: wilsonSurya
1 Replies
7. Shell Programming and Scripting
Hi,
I have a process that I run in the background that looks like this
${BASEDIR}/ksh/sqler.ksh ${compnames003} &
and I would like to get the return code of the sqler.ksh script.
so my code is like this
${BASEDIR}/ksh/sqler.ksh ${compnames003} &
retcode=$? (3 Replies)
Discussion started by: c19h28O2
3 Replies
8. Programming
two programs A and B writting in c++
I am using A to B and I want to know the return code of B.
in B
------------------------
int main()
{
return 11;
}
------------------------
in A
------------------------
int main()
{
system(A);
}
------------------------
Is it the right way... (1 Reply)
Discussion started by: filedeliver
1 Replies
9. UNIX for Advanced & Expert Users
two programs A and B writting in c++
I am using A to B and I want to know the return code of B.
in B
------------------------
int main()
{
return 11;
}
------------------------
in A
------------------------
int main()
{
system(A);
}
------------------------
Is it the right way... (1 Reply)
Discussion started by: filedeliver
1 Replies
10. Shell Programming and Scripting
Hi
I have the following piece of code that is calling another child process archive.ksh in the background
while read file;
do
file_name=`ls $file`;
ksh archive.ksh $file_name &;
done < $indirect_file
The problem is, indirect_file may contain anwhere from 2 to 20 different... (5 Replies)
Discussion started by: Vikas Sood
5 Replies
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 Also
execve(2), wait(2)
fork(2)