send input to netcat and save output












0














I am trying to send a command to netcat which will result into an output and I want to save that output to a file.



while true; do echo "showHistory userx"; done | nc -w1 xxx.xxx.xxx.xx 2222 > out.txt &


I tried a lot of google searches and read a lot of stackexchange questions but could not solve it. I played around with while, tee, mkfifo but no luck.



The file out.txt remains blank but has a lot of NUL chars



Edit: I have updated showhistory to showHistory userx in order to highlight that it is a command to be supplied over telnet/netcat session










share|improve this question
























  • You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
    – pfnuesel
    Feb 6 '18 at 22:49






  • 1




    If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
    – Sergiy Kolodyazhnyy
    Feb 6 '18 at 22:50






  • 1




    And I don't know why that showhistory is needed, but yes showhistory does the same.
    – pfnuesel
    Feb 6 '18 at 22:51
















0














I am trying to send a command to netcat which will result into an output and I want to save that output to a file.



while true; do echo "showHistory userx"; done | nc -w1 xxx.xxx.xxx.xx 2222 > out.txt &


I tried a lot of google searches and read a lot of stackexchange questions but could not solve it. I played around with while, tee, mkfifo but no luck.



The file out.txt remains blank but has a lot of NUL chars



Edit: I have updated showhistory to showHistory userx in order to highlight that it is a command to be supplied over telnet/netcat session










share|improve this question
























  • You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
    – pfnuesel
    Feb 6 '18 at 22:49






  • 1




    If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
    – Sergiy Kolodyazhnyy
    Feb 6 '18 at 22:50






  • 1




    And I don't know why that showhistory is needed, but yes showhistory does the same.
    – pfnuesel
    Feb 6 '18 at 22:51














0












0








0







I am trying to send a command to netcat which will result into an output and I want to save that output to a file.



while true; do echo "showHistory userx"; done | nc -w1 xxx.xxx.xxx.xx 2222 > out.txt &


I tried a lot of google searches and read a lot of stackexchange questions but could not solve it. I played around with while, tee, mkfifo but no luck.



The file out.txt remains blank but has a lot of NUL chars



Edit: I have updated showhistory to showHistory userx in order to highlight that it is a command to be supplied over telnet/netcat session










share|improve this question















I am trying to send a command to netcat which will result into an output and I want to save that output to a file.



while true; do echo "showHistory userx"; done | nc -w1 xxx.xxx.xxx.xx 2222 > out.txt &


I tried a lot of google searches and read a lot of stackexchange questions but could not solve it. I played around with while, tee, mkfifo but no luck.



The file out.txt remains blank but has a lot of NUL chars



Edit: I have updated showhistory to showHistory userx in order to highlight that it is a command to be supplied over telnet/netcat session







linux centos netcat






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Feb 6 '18 at 22:55







th3pirat3

















asked Feb 6 '18 at 22:44









th3pirat3th3pirat3

1013




1013












  • You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
    – pfnuesel
    Feb 6 '18 at 22:49






  • 1




    If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
    – Sergiy Kolodyazhnyy
    Feb 6 '18 at 22:50






  • 1




    And I don't know why that showhistory is needed, but yes showhistory does the same.
    – pfnuesel
    Feb 6 '18 at 22:51


















  • You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
    – pfnuesel
    Feb 6 '18 at 22:49






  • 1




    If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
    – Sergiy Kolodyazhnyy
    Feb 6 '18 at 22:50






  • 1




    And I don't know why that showhistory is needed, but yes showhistory does the same.
    – pfnuesel
    Feb 6 '18 at 22:51
















You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
– pfnuesel
Feb 6 '18 at 22:49




You might want to use &> instead of > to send both stdout and stderr to the file. Otherwise you have to be more precise about what is not working.
– pfnuesel
Feb 6 '18 at 22:49




1




1




If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
– Sergiy Kolodyazhnyy
Feb 6 '18 at 22:50




If I'm guessing right, your problem is that file is empty, right ? Quote from bash manual:"Background processes which attempt to read from (write to when stty tostop is in effect) the terminal are sent a SIGTTIN (SIGTTOU) signal by the kernel's terminal driver, which, unless caught, suspends the process". There's your reason - get rid of & part
– Sergiy Kolodyazhnyy
Feb 6 '18 at 22:50




1




1




And I don't know why that showhistory is needed, but yes showhistory does the same.
– pfnuesel
Feb 6 '18 at 22:51




And I don't know why that showhistory is needed, but yes showhistory does the same.
– pfnuesel
Feb 6 '18 at 22:51










1 Answer
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0














I've found smth like that



for port scanning output(ex. my router)



nc -zv 192.168.0.1 1-1000 2>&1 | grep open | tee report.txt


read a report



cat report.txt 


output



_gateway [192.168.0.1] 80 (http) open 
_gateway [192.168.0.1] 22 (ssh) open


In snapshotenter image description here






share|improve this answer








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    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    0














    I've found smth like that



    for port scanning output(ex. my router)



    nc -zv 192.168.0.1 1-1000 2>&1 | grep open | tee report.txt


    read a report



    cat report.txt 


    output



    _gateway [192.168.0.1] 80 (http) open 
    _gateway [192.168.0.1] 22 (ssh) open


    In snapshotenter image description here






    share|improve this answer








    New contributor




    Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.























      0














      I've found smth like that



      for port scanning output(ex. my router)



      nc -zv 192.168.0.1 1-1000 2>&1 | grep open | tee report.txt


      read a report



      cat report.txt 


      output



      _gateway [192.168.0.1] 80 (http) open 
      _gateway [192.168.0.1] 22 (ssh) open


      In snapshotenter image description here






      share|improve this answer








      New contributor




      Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





















        0












        0








        0






        I've found smth like that



        for port scanning output(ex. my router)



        nc -zv 192.168.0.1 1-1000 2>&1 | grep open | tee report.txt


        read a report



        cat report.txt 


        output



        _gateway [192.168.0.1] 80 (http) open 
        _gateway [192.168.0.1] 22 (ssh) open


        In snapshotenter image description here






        share|improve this answer








        New contributor




        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.









        I've found smth like that



        for port scanning output(ex. my router)



        nc -zv 192.168.0.1 1-1000 2>&1 | grep open | tee report.txt


        read a report



        cat report.txt 


        output



        _gateway [192.168.0.1] 80 (http) open 
        _gateway [192.168.0.1] 22 (ssh) open


        In snapshotenter image description here







        share|improve this answer








        New contributor




        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.









        share|improve this answer



        share|improve this answer






        New contributor




        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.









        answered Jan 8 at 1:14









        AlexAlex

        1




        1




        New contributor




        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.





        New contributor





        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.






        Alex is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
        Check out our Code of Conduct.






























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