Ensure builtin command is run under pathological circumstances












0















Given a hostile environment such as:



builtin()   { echo builtin function; }
command() { echo command function; }
type() { echo type function; }
unfunction(){ echo function unfunction; }
declare() { echo function declare; }

alias builtin=' echo builtin aliased #'
alias command=' echo command aliased #'
alias type=' echo type aliased #'
alias unfunction='echo unfunction aliased #'
alias declare=' echo declare aliased #'


Is it possible to access a builtin command? Eg, is it possible to do something like:



command builtin type echo


and still see:



echo is a shell builtin


Is possible for a hostile environment to be able to completely redefine things such that an underlying builtin, function or pathname could never be accessed?









share



























    0















    Given a hostile environment such as:



    builtin()   { echo builtin function; }
    command() { echo command function; }
    type() { echo type function; }
    unfunction(){ echo function unfunction; }
    declare() { echo function declare; }

    alias builtin=' echo builtin aliased #'
    alias command=' echo command aliased #'
    alias type=' echo type aliased #'
    alias unfunction='echo unfunction aliased #'
    alias declare=' echo declare aliased #'


    Is it possible to access a builtin command? Eg, is it possible to do something like:



    command builtin type echo


    and still see:



    echo is a shell builtin


    Is possible for a hostile environment to be able to completely redefine things such that an underlying builtin, function or pathname could never be accessed?









    share

























      0












      0








      0








      Given a hostile environment such as:



      builtin()   { echo builtin function; }
      command() { echo command function; }
      type() { echo type function; }
      unfunction(){ echo function unfunction; }
      declare() { echo function declare; }

      alias builtin=' echo builtin aliased #'
      alias command=' echo command aliased #'
      alias type=' echo type aliased #'
      alias unfunction='echo unfunction aliased #'
      alias declare=' echo declare aliased #'


      Is it possible to access a builtin command? Eg, is it possible to do something like:



      command builtin type echo


      and still see:



      echo is a shell builtin


      Is possible for a hostile environment to be able to completely redefine things such that an underlying builtin, function or pathname could never be accessed?









      share














      Given a hostile environment such as:



      builtin()   { echo builtin function; }
      command() { echo command function; }
      type() { echo type function; }
      unfunction(){ echo function unfunction; }
      declare() { echo function declare; }

      alias builtin=' echo builtin aliased #'
      alias command=' echo command aliased #'
      alias type=' echo type aliased #'
      alias unfunction='echo unfunction aliased #'
      alias declare=' echo declare aliased #'


      Is it possible to access a builtin command? Eg, is it possible to do something like:



      command builtin type echo


      and still see:



      echo is a shell builtin


      Is possible for a hostile environment to be able to completely redefine things such that an underlying builtin, function or pathname could never be accessed?







      bash shell zsh





      share












      share










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      share










      asked 1 min ago









      Tom HaleTom Hale

      6,85333694




      6,85333694






















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