10-03-2011
Are there devices on your network that have the same IP address? Were there any with this address before?
9 More Discussions You Might Find Interesting
1. Programming
Would anyone be so kind to explain to me the function of dup() in UNIX? As far as I am concerned, it duplicates a file descriptor. Under what circumstances would we need to duplicate a file descriptor in a UNIX environment?
Thank you.
vinchen (3 Replies)
Discussion started by: vinchen
3 Replies
2. Programming
I have met this code:
switch(fork()) {
case 0:
close(1);
dup(p);
close(p);
close(p);
execvp(<whatever>);
perror("Exec failed");
}
Can anyone tell me what this piece of code does?
Thx alot.. (1 Reply)
Discussion started by: AkumaTay
1 Replies
3. Programming
I'm having difficulty understanding the purposes of using dup/dup2 when involving forks.
for example, if we call fork() once, that is, we are creating a child process. In what cases would we need to use dup or dup2 to duplicate the file descriptors for standard output and standard error? What... (1 Reply)
Discussion started by: Yifan_Guo
1 Replies
4. Shell Programming and Scripting
Hi, I use this function (now modified with elif) for check if a pc is up: check_pc() {
$PING $PC 1 2> /dev/null
if ; then
check_dir #Other function
echo "Begin backup operation for $PC"
echo "$SMBTAR -s $PC -u $USER -p $PASS -x $SHARE$EXCL -t - | gzip -c >... (3 Replies)
Discussion started by: mbarberis
3 Replies
5. Programming
when i want to replace standard output with output file
int out;
out = open("out", O_WRONLY)p;
dup2(out,1);
What Shall I do in case of appending??? I am using here O_WRONLY TO WRITE.BUT IF i wanna append, whats the word? (5 Replies)
Discussion started by: joey
5 Replies
6. Shell Programming and Scripting
Hi,
I have a requirement where I have to identify duplicates from a file based on the first 6 chars (It is fixed width file of 12 chars length) and whenever a duplicate row is found, its original and duplicate row's last 2 chars should be updated to all 0's if they are not same. (I mean last 2... (3 Replies)
Discussion started by: farawaydsky
3 Replies
7. Shell Programming and Scripting
Hi Gurus,
I need to count the duplicate records in file
file
abc
abc
def
ghi
ghi
jkl
I want to get below result:
abc ,2
abc, 2
def ,1
ghi ,2
ghi, 2
jkl ,1
or
abc ,2
def ,1 (3 Replies)
Discussion started by: ken6503
3 Replies
8. Programming
help with bash script!
im am working on this script to make sure my server will stay online, so i made this script..
HOSTS="192.168.138.155"
COUNT=4
pingtest(){
for myhost in "$@"
do
ping -c "$COUNT" "$myhost" &&return 1
done
return 0
}
if pingtest $HOSTS
#100% failed... (4 Replies)
Discussion started by: mort3924
4 Replies
9. UNIX and Linux Applications
The problematic directory is the following:
/root/.cache/deja-dup
This directory grows until my "/" is full and then the restoring activity fails.
I already tried to create a symbolic link with origin another partition where I have more space. However during the restoring activity ... (4 Replies)
Discussion started by: puertas12
4 Replies
LEARN ABOUT REDHAT
ipcalc
IPCALC(1) RH IPCALC(1)
NAME
ipcalc - perform simple manipulation of IP addresses
SYNOPSIS
ipcalc [OPTION]... <IP address>[/prefix] [netmask]
DESCRIPTION
ipcalc provides a simple way to calculate IP information for a host. The various options specify what information ipcalc should display on
standard out. Multiple options may be specified. An IP address to operate on must always be specified. Most operations also require a
netmask or a CIDR prefix as well.
OPTIONS
-b, --broadcast
Display the broadcast address for the given IP address and netmask.
-h, --hostname
Display the hostname for the given IP address.
-m, --netmask
Calculate the netmask for the given IP address. It assumes that the IP address is in a complete class A, B, or C network. Many net-
works do not use the default netmasks, in which case an inappropriate value will be returned.
-p, --prefix
Show the prefix for the given mask/IP address.
-n, --network
Display the network address for the given IP address and netmask.
-s, --silent
Don't ever display error messages.
AUTHORS
Erik Troan <ewt@redhat.com>
Preston Brown <pbrown@redhat.com>
REPORTING BUGS
Report bugs to our bugtracking system: http://bugzilla.redhat.com/bugzilla.
COPYRIGHT
Copyright (C) 1997-2001 Red Hat, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
LAR PURPOSE.
SEE ALSO
ipcalc(3)
Red Hat, Inc. April 30 2001 IPCALC(1)