Programming :: Writing To And Reading From A Socket From Bash Script?
Mar 11, 2010
Here the description of the issue I am having.I am writing a bash test script which reads lines from a file, builds ISO messages, sends them to a server, reads the response with response code and reports the result of the test to a file or on the screen.The message that I need to send is 94 characters long.Here's the portion of a code that I initially wrote:
~ Open socket.
exec 3<>/dev/tcp/172.26.0.25/9991
#~ Send msg.
I would like to write a program that can read every ethernet frame arriving on a specific hardware NIC, without a TCP/IP stack otherwise doing anything on that NIC. Likewise I want to be able to write out to that NIC. So every arriving ethernet frame, of all types, would be readable (probably one at a time to preserve frame boundaries). And every write of exactly that same data would send frames out. The data read and written would be the whole ethernet frame. The kernel would do nothing else with this data, but other NICs would still operate as usual.
What I would be doing is that on 2 separate NICs, copying frames from one to the other, as in bridging. But I would also be doing modifications per what my program needs to do (not at liberty to say what that would be). What facility would I need to be looking at to do this? There is no ethernet device file. Would raw sockets be able to do this? The programming language will be C.
I am trying to read a file character wise and trying to write the same character to another file. In this process, I unable to read and write white spaces successfully to the new file. The script reads the white spaces but while writing the white space is lost. The section of the code, is given below. Please advice how can i read and retain the white space while writing to a new file.
Code:
if [ -s f_test.txt ] && [ -f f_test.txt ]; then echo "File Exists !!" while read -n1 char; do
There is the Archive::Zip I think I can use with Perl 5.10 but I don't know how. I don't want to read or write any files, just zip something in memory, with best compression, like
$text = "this is a test"; $zippedtext = &Zip($text); sub Zip {
Now in my bash script, I want to get the output /home/user instead of $HOME once read. So far, I have managed to get the $HOME variable but I can't get it to echo the variable. All I get is the output $HOME.
I have assignment to write bash script and I have to submit it after tommorow . I do not have experience to finish it by myself.I am really need help if any one can contact me. on my email I will be thanks him/ her.
I've been reading about getopt and getopts but it doesn't seem like it's possible to parse arguments like --foo or even -foo. I've started my own script trying to achieve this, but I'm still wondering if I'm losing performance and if there is a better way to do this task.
Also I'm using the [[ =~ ]] regex syntax which seems to be available only in newer bash versions, should it be a big issue? My bash version: GNU bash, version 4.1.7(2)-release (x86_64-unknown-linux-gnu)
I am trying to write a simple script to list all the files in a directory. The script I wrote was as below where the pdb_files is a directory and all the files which I want to list are in that folder.
Code: files=`ls -F pdb_files/*THERMO*` for inFiles in $files do echo $inFiles
I need to Read a path of a file witch is written in Text file i used this
Code:
FILENAME=$1 while read line do echo $line done < $FILENAME
it worked and showed me the Line witch was written in my file but now my problem is how am gonna use that line as a path i mean for example if am gonna execute a linux command on that file like dpkg -i /path/to/the/file how am gonna export it from The $Line variable and use it after the command.
how to program in bash, an i have a problem, i am trying compare values in between 2 values (from another file), so far my solution is to make a nested for loop, but that causes it to compare every value. Here is a visulization of what i want
file.a 2,3,4,5 file.b 3 5
[code]...
i want the values 2, 3, 4, 5 from file.a to be compared inbetween values 3 5, 6 9,1 2, 4 7 from file.b (var1 is the value im comparing, var2 is the less value, var 3 is the greater value)
for i in $var1 do for k in $var2 do
[code]....
my problem with the above code is it compares EVERYINNG, not the values inbetween what i want (which is 3 5, 6 9 etc).
I would like to read unix file permissions into a bash array for processing but tbh I have no idea how to do this. Then I will check for each individual access right l, d, x etc.
I have been trying to write a simple snip of bash shell code to import from 1 to 100 records into a Bash array.
I have a CSV file that is structured like: record1,item1,item2,item3,item4 record2,item1,item2,item3,item4 record3,item1,item2,item3,item4 record4,item1,item2,item3,item4
And would like to get this data into corresponding arrays as such: $record1[item1-4] $record2[item1-4] $record3[item1-4] $record4[item1-4]
iam just trying to connect to server which accepts one client and server will read(blocking operation) infinitely, but After closing the client socket the server "read operation" is returning zero and "errno variable(in errno.h)" value is also zero. how can i detect whether a client socket is closed/active..?
I've been able to get access to our Netgear NAS, I can browse it, copy files etc. just fine. But I don't have "direct access" in as far as, Open Office won't open any files residing on the NAS, neither can I save directly to the NAS form a program and when I get a "Browse for File" form field on a website (eg attachments in GMail etc.), I can't browse to the NAS either. My XP box does do all of this, either through my mapped network drive or even through browsing the network. How can I make openSuse 11.2 use the NAS with my login credentials as if it was a local disk?
I've used ext2ifs drivers to mount my ext3 partition in winxp, but I don't have write acces, it's mounted in a read-only mode, and i didn't check the rad-only box during the installation of the drivers. [URL] It's a straithfoward proces so I dont understand what I did wrong. I'm using fresh xp install with (more or less) all the updates and ubuntu 10.04 Also the partition is mounted at /home, so I dont know if that makes any difference.
I've used ext2ifs drivers to mount my ext3 partition in winxp, but I don't have write acces, it's mounted in a read-only mode, and i didn't check the rad-only box during the installation of the drivers.I've used help from the official site http://www.fs-driver.org/and this tutorial http://www.dedoimedo.com/computers/l...s-windows.html It's a straithfoward proces so I dont understand what I did wrong.I'm using fresh xp install with (more or less) all the updates and ubuntu 10.04Also the partition is mounted at /home, so I dont know if that makes any diferance.
My main workstation incorporates a mixture of ext3, ext4, and NTFS partitions scattered across a number of hard drives. Several of the ext4 partitions are encrypted, and I intend to encrypt the rest of the Linux partitions in the near future.I run VMware workstation, with several Windows OS guests, including Win2K, WinXP and Win7. My Win7 VM is installed on a virtual hard disk, and that virtual hard disk is encrypted using VMware facilities.So this leaves me with a bunch of NTFS partitions that are not encrypted. These are physical partitions on a couple of different hard drives. The reason I have them is ancient and historical, and as I have upgraded my system over time I have maintained the architecture due to the extreme difficulty of rearranging Windows systems.I still need to maintain Win2K and WinXP support, and rearranging those virtual machines would represent a hideous nightmare for me; I really want to maintain the same hard drive partition architecture.But I want to encrypt the NTFS partitions, in a fashion that can be handled by any of the Windows operating systems, AND can be accessed for read and write from Linux.Is this possible? If not using Windows facilities (I don't think ntfs-3g handles encryption, and there are known backdoors in the Windows facilities anyway), is there any third party solution that would work? Would True Crypt do the job in a fashion that would permit access from all the various operating systems, as required? I do generally mount the NTFS partitions in whichever Windows VM is appropriate, then share them out via SMB, but there are circumstances (like when a VM is not running) where I will directly hit them from Linux. So, it is possible for me to contemplate a solution that only works from Windows, but this would cost me the ability to repair/modify those filesystems directly from Linux, which under certain circumstances (a malfunction of the VM, for instance) could be a problem.
I am about to write a program to listen and read data from /dev/ttyS0 and write the data to /dev/ttyS1 after processing. Also, the same time I need to listen to /dev/ttyS1 and write to /dev/ttyS0 if any data arrived at /dev/ttyS1.
I want to be able to access my email account from the console. I'm reading all day about fetchmail, postfix, sendmail etc. but all the stuff I found is related to building whole mail system. All I want to do is to read my emails and write some. Which is the painless way to do this? I successfully configured Evolution for this purpose but I want to do that from the console.
At times I see heavy hard-disk activity slowing down system.I have enough RAM and enough of it free.Apparently I am not doing anything that should cause this.'vmstat' shows high numbers for "bi bo" I want to find out which processes are doing "bi bo".How can I zero in on the particular processes?What command?
the above code works fine.if we copmile and run ./a.exe 192.xx.xx.xxx 1111 and press enter it works fine..everytime it asks "Please enter the message: " and if give that will be displayed in server. but my problem is i dont want to print everytime "Please enter the message: " i just want to feed some words one by one to the socket.
im getting that error in my code for some reason. I compiled my code, and when i try to run this server it throws me an error on my call to setsocketopt(). The only way it can reach that part of my loop is if it succeeds when it calls sock() so I dont understand why the error says its an operation on a non-socket. Im just trying to set up a server to pass messages from a client to it a viceversa. Here is the code:
Code: int main() { int socket_fd, new_socket_fd, k; struct addrinfo hints, *server_info, *p; struct sockaddr_storage peer_address; code....
