Write To Pipe File Hangs (using Echo Command)

I understand how to use the write command but I'm unsure about how to set up the users. If my friend in inThe uk and I'm in the USA is it possible for me to write to him via the terminal with the write command or is it only for a local network within my office?

How do I set up the people who I want to talk with via the write command? I'm looking online but everyone seems to address the question presuming the users are already set up.

hey guys,

Let's say I want to find out which log files have related ntp information in them. I use cat and grep to search through the files in /var/log and then export that to a file. this is the command...

# cat /var/log/* | grep ntp > /home/log.txt

The file created from this command will not include the directories the log entries are apart of. Why not? For example, if you do this same command without exporting to the /home/log.txt file it will show you in stdout which directory each log entry is in. Hope I'm making sense here. My question is, is there a clever way to export to a file in a way so that the file created is structured exactly like the stdout of the command below?

# cat /var/log/* | grep ntp

I have many hosts as following. But those hosts are dual operating system (Linux and Windows). I always run program background. If someone is using Linux, it is fine. But if someone is using windows or the host is offline. Then, I cannot use ssh. The way I do preiviously is first ssh one by one. And then find the hosts which are offline or windows. And write them down one by one. And then ssh to hosts except them. Let us assume the number of programs is less than the total available hosts. Can someone write a shell script to output the all available hosts to a file like "host_available"?
Here is the host file.
https://www.dropbox.com/s/vbz6w864y3...tlist.txt?dl=0
I am using ssh to connect the computers on campus. If the computer I am trying to connect is offline or using windows, the ssh will take long time, and finally it will failed. I write a shell script to generate the hostlist
Code:

#!/bin/bash
for i in `seq -w 1 28`
do
echo "c15-0330-$i.ad.mtu.edu"
# I would like to add a command here to see whether ssh c15-0330-$i.ad.mtu.edu it succeeds or not. And then output a #file which contains the all available host.
done
for i in `seq -w 1 20`
do
echo "c28-0112-$i.ad.mtu.edu"
done
for i in `seq -w 1 20`
do
echo "c28-112a-$i.ad.mtu.edu"
done

I do not how to set a certain time to see whether connection is successful or not (see the comment in the shell script).

I am writing a pythong program which has command line executions for linux like ls and restart. I want to know how to pass the errors from the command executed to a file so that it becomes a log.

Hi All..

I need to give four lines of gap(Freespace) between two command outputs.

what i did was below

Code:

echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
print "***************** LEVEL 2: Truncating  Tables: Success:  tables Truncated ***********************" >> $LOG/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
echo "" >>$LOG_DIR/$LOG_NAME
# Run the load scripts.
echo "***************** LEVEL 3: Loading Dupe Check Tables: Success: Dupe Check tables Loaded***********************" >> $LOG/$LOG_NAME

Is there any better way of writing this command to leave multiple lines between two commands.

Please advise...

I am trying to develop a new routing protocol in ns2. Although i have given a command in tcl file that should be called from command function present in .cc file. But it is not doing so.
Could we debug this and find the point where is the problem. If yes then how ?

I have heard that there are debuggers in ns2 . But this is for tcl or c++ ....
Could any one please help me ... How can i proceed further.

Thanks for ur help

Hello, I have an expect script where I ssh to a remote host to determine the network configuration and get from the user the network interface card that should be used. From their response, I determine the subnet mask and save the information to a text file that is later transmitted back to my local host. This is all so that I can set up virtual IP aliasing and verify that the physical IP address of the local and remote host are on the same subnet prior to continuing with the setup. I am running the script on Linux, with expect version 5.45.

The code itelf works just fine, but I'm having some issues with how it displays on the screen. As you'll see below in the example, the default system prompt displays, as does the user input command that I'm sending to the shell from the expect script.

Is there a regular expression or something that I can write to prevent the prompt and command that I'm sending from printing to the screen? I know that it should be suppressed if I have an expect command following the Code:

send -s "\nread n_card?'Enter the network interface card number for this server (i.e. eth0):   '\r

command, but everything I have tried for strings and regular expressions to expect causes the netstat -rn output to not show up all of a sudden. I'm new to expect, so I'm not really sure why this is happening.

I would really appreciate any help/suggestions. Thanks for your time!

Part of the Script Code:
Code:

expect {
   -re $prompt {   ;# Send individual commands and get user input
        set timeout -1
        
        # Get partner hostname and put in vipsetup.txt file
        send -s "hostname > vipsetup.txt\r"  
        expect -re $prompt
        
        # Display the network routing info for the user and prompt for 
        # network interface card number
        send -s "print \"The network routing table for the $ptner server is displayed below:\n\" ; netstat -rn \r"
        
        expect -re "\r(.*):\r"
        send -s "\nread n_card?'Enter the network interface card number for this server (i.e. eth0):   '\r"
        interact "\r" return    ;# Wait for user input from read command
        send -- "\r"
        send -s "echo \$n_card >> vipsetup.txt\r"  
        
        # Obtain subnet mask information for partner based on network 
        # interface card number being used
        send -s "msk=\$(cat /etc/sysconfig/network-scripts/ifcfg-\$n_card | grep NETMASK)\r"
        send -s "msk=\$(echo \${msk#NETMASK=})\r"
        send -s "echo \$msk >> vipsetup.txt\r"
    }
    timeout {
        send_user "Connection to host $hostip timed out."
        exit 6 
    }
    eof {
        send_user "Connection to host $hostip failed."
        exit
    }
}

Script Output:
Code:

The network routing table for the PRIMARY server is displayed below:
 
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
10.105.65.0     0.0.0.0         255.255.255.0   U         0 0          0 eth0
0.0.0.0         10.105.65.1     0.0.0.0         UG        0 0          0 eth0
 [root@remotehost root]$
[root@remotehost root]$ ber for this server (i.e. eth0):   '              < 
Enter the network interface card number for this server (i.e. eth0):   eth0

Hello--

I'm trying to locate a file or a command line in a file on my hard drive. I am running Ubuntu 12.05.4 linux. Is there a grep command that will search the whole tree from root down to all the sub-directories?

Thank You.

Hi,

I have been trying to get information on how to process the output of a tcl file (aodv and leach protocol using mannasim) which I got on my command line Iinterface. Actually, I don't even know the keywords to search as I am new to this and other minor attempts haven't yielded positive results., I know there is usually a trace file but I can't see any. All I see is on my command line.

I also observe that it took the space on the entire screen and I can't copy the output from the start ( I could only copy from node 19 out of 30 nodes) because of the huge number of output lines.

The last thing I havent been able to figure ou is whether temperature is equivalent to energy Iin mannasim as mannasim has only temperature and carbon dioxide?


Thanks

I want to write a bash shell script to execute a command for one minute then stop that command (ctrl c) pause for 10 seconds then run another command for one minute then stop that command pause for 10 seconds then go back to the begining of the script and loop indefinetly.

First I want to run this command for one minute;

reaver -i mon0 -c 6 -b "mac address" -a -vv

stop previous command and pause for 10 seconds

Then run this command for one minute;

airodump-ng -i mon0

stop previous command and pause for 10 seconds

Then recall reaver command and continue to loop through until reaver spits out result.

I imagine I will need to create a function for each command, an if statement and an ifelse statement and I will need the break and sleep commands. but I am not sure about the syntax, PLEASE HELP THIS NOOB!