I am trying a bit of experiments with airmon-ng script in Linux. Meanwhile i want to redirect output of a process "airodump-ng mon0" to a file. I can see the instantaneous output on the screen. The feature of this process is that it won't stop execution(actually it is a script to scan for AP and clients, it will keep on scanning) unless we use ctrl+c.
Whenever i try
airodump-ng mon0 > file.txt
i won't get the output in the file.
My primary assumption is that the shell will write it to the file only after completing the execution. But in the above case i stopped the execution(as the execution won't complete).
So to generalize i can't pipe the output of a running process to a file. How can i do that?
Or is there any alternative way to stop the execution of the process(for example after 5 seconds) and redirect the current output to a file?
A process may send output to standard output or standard error to get it to the terminal. Generally, the former is for information and the latter for errors, but in some cases, a process may mix them up.
I'm supposing that in your case, the standard error is being used. To get both of these to the output file, you can use:
airmon-ng mon0 > file.txt 2>&1
This says to send standard output to file.txt and to reroute 2 (which is the file id for standard error) into 1 (the file id for standard output) so that it also goes to the file.
Related
How can I run a binary cgi file on the command line and provide GET parameters to it?
I understand this task may be straightforward for perl or php files, but I've got a binary cgi file and no documentation for it. I'd like to run it without a web server so that I can evaluate certain problems on some co-workers' machines.
I've tried the following, but to no avail:
QUERY_STRING="foo=bar" ./myfile.cgi
foo=bar ./myfile.cgi
./myfile.cgi foo=bar
./myfile.cgi <<< "foo=bar"
In each case, the script outputs Error in form found<br>Missing foo<br><b></b><br>. (When executed through apache on our server, it returns no error message, only the intended results.)
Specifying the environment variable REQUEST_METHOD=GET in addition to QUERY_STRING=... makes the difference.
Among the tokens output by strings myfile.cgi, there were a number of cgi-related variables which the web server might be expected to set, such as REMOTE_ADDR, SERVER_SOFTWARE, and SERVER_PROTOCOL, but the two aforementioned variables proved enough to get this executable to produce a non-error output.
(For a POST, I've read that the body/params are read from stdin, but I haven't substantiated that personally.)
I am very new to creating batch files.
I have to run a command, with an increasing file number e.g
c:>program.bat -propertyfile "1.property"
Right now, I have to type the command manually, wait 1 minute, then type the command again by increasing the property file # i.e "2.property" "3.property" "4.property" etc....
I want to automate this, and still would like to see the results in the command prompt as it runs.
How can this be accomplished?
See https://ss64.com/nt/for.html and specifically https://ss64.com/nt/for_l.html
FOR /L %%G IN (1,1,4) DO program.bat -propertyfile "%%G.property"
Should run your command for files 1.property to 4.property but if you're actually running it for files in a directory rather than a list of integers one of the other FOR constructs might be more appropriate. Perhaps https://ss64.com/nt/for_r.html
I workin' with Torch7 and Lua programming languages. I need a command that redirects the output of my console to a file, instead of printing it into my shell.
For example, in Linux, when you type:
$ ls > dir.txt
The system will print the output of the command "ls" to the file dir.txt, instead of printing it to the default output console.
I need a similar command for Lua. Does anyone know it?
[EDIT] An user suggests to me that this operation is called piping. So, the question should be: "How to make piping in Lua?"
[EDIT2] I would use this # command to do:
$ torch 'my_program' # printed_output.txt
Have a look here -> http://www.lua.org/pil/21.1.html
io.write seems to be what you are looking for.
Lua has no default function to create a file from the console output.
If your applications logs its output -which you're probably trying to do-, it will only be possible to do this by modifying the Lua C++ source code.
If your internal system has access to the output of the console, you could do something similar to this (and set it on a timer, so it runs every 25ms or so):
dumpoutput = function()
local file = io.write([path to file dump here], "w+")
for i, line in ipairs ([console output function]) do
file:write("\n"..line);
end
end
Note that the console output function has to store the output of the console in a table.
To clear the console at the end, just do os.execute( "cls" ).
I have a script which interacts with user (prints some questions to stderr and gets input from stdin) and then prints some data to stdin. I want to put the output of the script to a variable in vimscript. It probably should look like this:
let a = system("./script")
The supposed behavior is that script runs, interacts with user, and after all a is assigned with its output to stdout. But instead a is assigned both with outputs to stdout and stderr, so user seed no prompts.
Could you help me fixing it?
Interactive commands are best avoided from within Vim; especially with GVIM (on Windows), a new console window pops up; you may not have a fully functional terminal, ...
Better query any needed arguments in Vimscript itself (with input(); or pass them on from a custom Vim :command), and just use the external script non-interactively, feeding it everything it needs.
What gets captured by system() (as well as :!) is controlled by the 'shellredir' option. Its usual value, >%s 2>&1 captures stdout as well as stderr. Your script needs to choose one (e.g. stdout) for its output, and the other for user interaction, and the Vimscript wrapper that invokes it must (temporarily) change the option.
:let save_shellredir = &shellredir
:set shellredir=>
:let a = system('./script') " The script should interact via stderr.
:let &shellredir = save_shellredir
Call the script within the other as,
. ./script.sh
I think this is what you meant.
The title says it all.
I have 4 awk processes logging to the same file, and output seems fine, not mangled, but I'm not sure that just redirecting print output like this: print "xxx" >> file in every process is the right way to do it.
There are many similar questions around the site, but this one is particularly about awk and a pragmatic, code-correct way to approach the problem.
EDIT
Sorry folks, of course I wasn't "just redirecting" like I wrote, I was appending.
No it is not safe.
the awk print "foo" > "file" will open the file and overwrite the file content, till the end of script.
That is, if your 4 awk processes started writing to the same file on different time, they overwrite the result of each other.
To reproduce it, you could start two (or more) awk like this:
awk '{while(++i<9){system("sleep 2");print "p1">"file"}}' <<<"" &
awk '{while(++i<9){system("sleep 2");print "p2">"file"}}' <<<"" &
and same time you monitoring the content of file, you will see finally there are not exactly 8 "p1" and 8 "p2".
using >> could avoid the losing of entries. but the entry sequence from 4 processes could be messed up.
EDIT
Ok, the > was a typo.
I don't know why you really need 4 processes to write into same file. as I said, with >>, the entries won't get lost (if you awk scripts works correctly). however personally I won't do in this way. If I have to have 4 processes, i would write to different files. well I don't know your requirement, just speaking in general.
outputting to different files make the testing, debugging easier.. imagine when one of your processes had problem, you want to solve it. etc...
I think using the operating system print command is save. As in fact this will append the file write buffer with the string you provide as log. So the system will menage the actual writing process of the data to disc, also if another process will want to use the same file the system will see that the resource is already claimed and will wait for 1st thread to finish its processing, than will allow the 2nd process to write to the buffer.