Forking and Pinging

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Pinging 5 hosts once every hour

Hello folks; I'm trying to write a shell script to ping 5 hosts i have once every 1 hour and if it receives any failure from any of those hosts, it sends an email alert with the results from this failing ping. Any help would be greatly appreciated

2. Emergency UNIX and Linux Support

Script for pinging continuously

Hi, I need to set up a script that would write the results of the ping command from one AIX server to another file may be every minute. Like this I need to gather the data for a period of 24 hours. Can someone please help me with this? G

3. UNIX Desktop Questions & Answers

Pinging Host

I need to ping websites and I need to see which one has the highest delay. My problem is I need to extract the name Facebook and the time=74.0 ms using awk. I need help doing this please... PING facebook.com (173.252.90.36) 56(84) bytes of data. 64 bytes from...

4. IP Networking

Pinging IP located on another interface

Hi, I have a rather strange IP question... Here's my problem: I have a Linux box (call it "turing") with 2 NICs. One network interface (eth0) has an IP assigned, say 192.168.42.50. The other interface (eth1) is up, but has no IP yet. My question: is it possible to determine from...

5. Shell Programming and Scripting

Pinging a domain

how can you ping a domain and store the ip? like given a url in a variable $url how can i ping it? also how can i find the local server's ip address on a cpanel server? (i have multiple servers and didnt want to hard code it in) (basically i want to check the domain accounts on the server,...

6. Solaris

Server Pinging Problem

Dear all, I face some problem as below. I have a sun fire 280r server in a network. From that server i am able to ping any system in any network. But i am facing the problem when i try to ping the server from outside netwok. Once i give ping command in the server then only i try to...

7. UNIX for Advanced & Expert Users

Alternate to pinging boxes

Hello, We have boxes on a WAN network I guess you would call it, pretty much they are hooked up via DSL in different locations in the US and we connect to them via SSH for a secure connection. Some of the boxes won't return a ping request like they are down, I am guessing is because the router...

8. Shell Programming and Scripting

pinging an ip

Hi, How to ping an ip from an unix machine. Can you please let me know the exact command. I used and i got the below error ping 171.18.17.2 bash: ping: command not found Thanks n regards Ammu

9. AIX

pinging IP's in a file

Hey all. I have a long list of IP addresses I want to ping. The IP's are located in a flat file "ping_info.dat". I was wondering what the best way to go about this would be. Can someone help me out?

10. UNIX for Advanced & Expert Users

Server stopped pinging (in and out)

hi All my Redhat Linux server stopped responding to pings all together. and am also not able to ping out of the box. There are however no issues with internet connectivity and my application is working fine. When I tried to ping another machine (Win98) i could see the pings coming from my...

LEARN ABOUT NETBSD

fork

FORK(2) 						      BSD System Calls Manual							   FORK(2)

NAME

     fork -- create a new process

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <unistd.h>

     pid_t
     fork(void);

DESCRIPTION

     fork() causes creation of a new process.  The new process (child process) is an exact copy of the calling process (parent process) except for
     the following:

	   o   The child process has a unique process ID.

	   o   The child process has a different parent process ID (i.e., 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 an lseek(2) on a descriptor in the
	       child process can affect a subsequent read(2) or write(2) 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 process' resource utilizations are set to 0; see setrlimit(2).

     In general, the child process should call _exit(2) rather than exit(3).  Otherwise, any stdio buffers that exist both in the parent and child
     will be flushed twice.  Similarly, _exit(2) should be used to prevent atexit(3) routines from being called twice (once in the parent and once
     in the child).

     In case of a threaded program, only the thread calling fork() is still running in the child processes.

     Child processes of a threaded program have additional restrictions, a child must only call functions that are async-signal-safe.  Very few
     functions are asynchronously safe and applications should make sure they call exec(3) as soon as possible.

RETURN VALUES

     Upon successful completion, fork() 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.

ERRORS

     fork() will fail and no child process will be created if:

     [EAGAIN]  The system-imposed limit on the total number of processes under execution would be exceeded.  This limit is configuration-depen-
	       dent.

     [EAGAIN]  The limit RLIMIT_NPROC on the total number of processes under execution by this user id would be exceeded.

     [ENOMEM]  There is insufficient swap space for the new process.

SEE ALSO

     execve(2), setrlimit(2), vfork(2), wait(2), pthread_atfork(3)

STANDARDS

     The fork() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

HISTORY

     A fork() system call appeared in Version 6 AT&T UNIX.

BSD
								   June 10, 2004							       BSD

Shell Programming and Scripting