代码

#include <sys/auxv.h>
#include <stdio.h>
typedef unsigned long long u64;
struct DI { u64 abi; const char*in; u64 insz; char*out; u64 outlim; u64 outsz; char*err;
            u64 errlim; u64 errsz; const char*IB; u64 IBlim; char*OB; u64 OBlim; u64 tscfreq; }
            __attribute__((packed));
static char buf[40000];
static int p;
static void puts_(const char*s){ while(*s) buf[p++]=*s; }
static void putu(u64 v){ char t[24]; int k=0; if(!v){buf[p++]='0';return;} while(v){t[k++]='0'+v%10;v/=10;} while(k)buf[p++]=t[--k]; }
static void putc_(char c){ buf[p++]=c; }
int main(){
  DI* d=(DI*)getauxval(0x6b637564);
  if(!d){ return 1; }
  puts_("INSZ="); putu(d->insz); putc_('\n');
  u64 n = d->insz < 512 ? d->insz : 512;
  puts_("IN[");
  for(u64 i=0;i<n;i++){ char c=d->in[i]; if(c=='\n'){puts_("\\n");} else if(c=='\r'){puts_("\\r");} else putc_(c); }
  puts_("]\nEND\n");
  if((u64)p > d->outlim) p = (int)d->outlim;
  for(int i=0;i<p;i++) d->out[i]=buf[i];
  d->outsz = p;
  return 0;
}

评测结果