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|improve this question























  • unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

    – Michael Homer
    18 mins ago
















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|improve this question























  • unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

    – Michael Homer
    18 mins ago














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|improve this question














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|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 34 mins ago









Tom HaleTom Hale

6,85333694




6,85333694













  • unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

    – Michael Homer
    18 mins ago



















  • unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

    – Michael Homer
    18 mins ago

















unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

– Michael Homer
18 mins ago





unalias builtin; unset -f builtin? I don't think this environment is hostile enough.

– Michael Homer
18 mins ago










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