void main(){
    struct stat time_buf;
    time_t input_timestamp=0;

    while(1){
        if(access( "inpfile.txt", F_OK ) != -1){
            sleep(5);
            stat("inpfile.txt", &time_buf);
            if(time_buf.st_mtime > input_timestamp){
                FILE *fpi,*fpo;
                long length;
                char *buffer=0;
                fpi = fopen("inpfile.txt","r");
                fseek(fpi,0,SEEK_END);
                length=ftell(fpi);
                fseek(fpi,0,SEEK_SET);
                buffer=(char *)malloc(length);
                fread(buffer,1,length,fpi);
                fclose(fpi);

                fpo=fopen("outfile.txt","w+");
                fwrite(buffer,sizeof(char),length,fpo);
                fclose(fpo);
                input_timestamp=time_buf.st_mtime;
            }
        }
    }

}