Thanks！ I've found statement in intrpvar.h: PERLVAR(I, stack_sp, SV **) /* top of the stack */ and in perl.h: 
#  define PERLVAR(prefix,var,type) type prefix##var;

/* 'var' is an array of length 'n' */
#  define PERLVARA(prefix,var,n,type) type prefix##var[n];

/* initialize 'var' to init' */
#  define PERLVARI(prefix,var,type,init) type prefix##var;

/* like PERLVARI, but make 'var' a const */
#  define PERLVARIC(prefix,var,type,init) type prefix##var;

struct interpreter {
#  include "intrpvar.h" 
};

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So perl use PERLVAR to define perlinterpreter struct, it's strange to me, why is it not define perlinterpreter structure directly in perl.h? Please enlighten me.


I am trying to improve my English skills, if you see a mistake please feel free to reply or /msg me a correction

In reply to Re^2: what definition of Istack_sp by xiaoyafeng
in thread what definition of Istack_sp by xiaoyafeng

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