I’m going to implement a firewall on the traffic control classifier(man 8 tc-bpf). The firewall is to filter outgoing traffic. But, there is one point which makes the task really hard. My userspace agent must know, is that filter(classifier) loaded and passing all outgoing traffic through itself or not.…
Tag: linux
How to print the content of a text file to STDOUT in Linux Assembly Language using c library functions?
First I tried opening a file with fopen function and print content of the file using fprint function but it was just printing a bunch of symbols to the terminal. After a while I realized that it does not take pointer to a stream as argument and above mentioned behaviour was expected. It was printing the actua…
Current path is not showing in terminal for new CentOS user [closed]
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers. This question does not appear to be about a specific programming problem, a software algorithm, or software tools primarily used by programmers. If you believe the question would be on-topic on another Stack …
How to extract the directory from full file path
I have the following script which prints various file stats, which was kindly supplied by another user (choroba) (link). Is there a way that this can be amended to report just the directory name of each file and not the full file path with the file name? I have tried changing filepath with dirname and I get a…
Permission denied – Even tho in group with ownership [closed]
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How can I extract parameters of curl request and append them to beginning of txt file using bash
I have a bash file which is executed every 5 seconds, it goes like this: It pings to a server running in a neighbor Virtual Machine and records the curl response into the specified file “debian0_ping.txt” but the recorded response looks like this: Which is a problem because I need the pings respon…
Wrapper script that write logs of arguments, stdin and stdout
I want to create a wrapper script which writes logs of arguments, stdin and stdout. I have written the following script wrapper.sh, which works almost fine. I expect that ./wrapper.sh arg1 arg2 gives the same result as /path/to/command arg1 arg2 with logs in /tmp/stdio-log/. But it gives a slightly different …
How to include comments from Nmap script in the output file
There might be a better way to do this, but what I have is an input file called “list.txt” of IP addresses for my Nmap scan like so: Then I scan with Nmap using and output to a file using: Additionally I have used sed to make the “output.txt” look like this: I would like to include the…
CLPPLUS login failing
I am trying to login to remote DB2 using clpplus but can’t login as password contains @. clpplus -nw user/p@sswd@145.xx.xx.212:60000/Dbname but it fails saying: Is there any work around of it? Answer With the bash shell, enclose the password with ‘ and additionally escape the @ with @ (and the sam…
Setting both read() and send() timeouts for the same C socket on linux
I managed to set a read timeout for a C socket with: Now, I want to make this same socket timeouts for send operations. I have found in setsockopt that the proper way to set a timeout for send is quite similar, just replacing SO_RCVTIMEO by SO_SNDTIMEO: My question is if does a successive call of setsockopt o…