wr.c (C wrapper):

#include <unistd.h>
main(int argc, char* argv[])
{
   char* sArgv[8];
   sArgv[0] = (char*)"/usr/bin/perl";
   sArgv[1] = (char*)"-wT";
   sArgv[2] = (char*)"/home/fred/setuid/t1.pl";
   sArgv[3] = argv[1];
   sArgv[4] = 0;
   execv("/usr/bin/perl", sArgv);
}