[erlang-questions] How to get the line number of current executable code?

Ahmed Ali <>
Tue Aug 26 21:05:10 CEST 2008


Hi Mats,

I've seen process_display(Pid, backtrace) but never thought to use it
this way. Thanks for the insight.

Best regards,

Ahmed Al-Issaei

On Tue, Aug 26, 2008 at 12:54 PM, Mats Cronqvist
<> wrote:
> Richard Carlsson wrote:
>>
>> Ahmed Ali wrote:
>>
>>>
>>> Hi All,
>>>
>>> This discussion is interesting. Just wanted to know if it is possible
>>> to get the function that called current function. Is this possible?
>>>
>>
>> The only way of doing that is to force an exception, and then look
>> at the stack trace.
>
>  there is no way to reliably get the name of the calling function.
>  it is true that the stack sometimes contain the name of the calling
> function.
>  it is not true that the only way to inspect the stack is by forcing an
> exception.
>
>  i'm too lazy to write actual code, but try this in the shell;
>
> ()41> {_,BT}=erlang:process_info(self(),backtrace).
> ()42> S=fun(B,{_,[_,{F,L}|_]})->
> <<_:F/binary,R:L/binary,_/binary>> =B, R end.
> ()43> S(BT,re:run(BT,"Return addr\\s[0-9a-z]+\\s\\(([^\\s]*)")).
> <<"erl_eval:expr/5">>
>
>  clear as the day!
>
>  mats
>



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