用c写了个后台扫描

/**
 * Notice: The program is not debug on internet and not use thread supervene.
 * date  : 6-26
 * author: jker
 **/
#include <sys/socket.h>
#include <stdio.h>
#include <netinet/in.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#define LINE 1024
#define dict "dict.txt"
#define result "manager.txt"

void itos(int num,char *str){
  int a=num;
  int x,y,z;
  x=a/;
  y=a%/;
  z=a%;
  if(x==){
    if(y==){
      str[]+=z;
      str[]='\0';
    }else{
      str[]+=y;
      str[]+=z;
      str[]='\0';
    }
  }else{
    str[]+=x;
    str[]+=y;
    str[]+=z;
    str[]='\0';
  }
  return;
}
char *nip(char *oip){
  char *str[]={""},*rtn;
  char *delim = ".";
  char * tmp;
  int i=;
  char arr[]={,,,'\0'};
  rtn = malloc();
  memset(rtn,'\0',);
  tmp = strtok(oip,delim);
  str[i++]=tmp;
  while(tmp=strtok(NULL,delim)){
    str[i++]=tmp;
  }

  for(i=;i>=;i--){
    if(atoi(str[i])<){
      itos(atoi(str[i])+,arr);
      str[i]=arr;
      break;
    }
  }

  for(i=;i<;i++){
    strcat(rtn,str[i]);
    if(i<)strcat(rtn,delim);
  }

  return rtn;
}
int main(int argc,char *argv[]){
  int sc,fd;
  unsigned short port = ;
  struct sockaddr_in add;
  char *ip,*sip,*eip;
  struct hostent *host;
  char rheader[LINE],dictbuf[LINE],resbuf[LINE];
  char *dir,path[LINE]="",*arr[LINE],*tmp,state[],manager[LINE];
  int i=,n=,bytes;
  if(argc != ){
    printf("please input startIp and endIp.\r\n");
    return -;
  }
  dir = get_current_dir_name();
  strcat(path,dir);
  strcat(path,"/");
  strcat(path,dict);
  fd = open(path,O_RDONLY);
  read(fd,dictbuf,sizeof(dictbuf));
  close(fd);
  arr[n++]=strtok(dictbuf,"\r\n");
  while(tmp=strtok(NULL,"\r\n"))arr[n++]=tmp;

  ip = malloc();
  memset(ip,'\0',);
  sip = argv[];
  eip = argv[];
  strcpy(ip,sip);

  memset(manager,'\0',LINE);
  memset(rheader,'\0',LINE);

  sc = socket(AF_INET,SOCK_STREAM,);
  if(sc == -){
    printf("create socket fail!\r\n");
    return -;
  }
  printf("create socket ok.\r\n");
  bzero(&add,sizeof(add));
  add.sin_family=AF_INET;
  add.sin_port=htons(port);
  bzero(&path,sizeof(path));
  strcat(path,dir);
  strcat(path,"/");
  strcat(path,result);
  fd = open(path,O_WRONLY|O_CREAT);

  do{
    host = gethostbyaddr(ip,strlen(ip),AF_INET);
    if(host == (struct hostent *)NULL) {
      printf("can`t get host from %s\r\n",ip);
      if(strcmp(ip,eip)<)ip=nip(ip);
      continue;
    }else{
      printf("host name:%s\n",host->h_name);
    }

    add.sin_addr.s_addr=inet_addr(ip);
    if(connect(sc,(struct sockaddr *)(&add),sizeof(struct sockaddr))==-){
      printf("conn fail!\r\n");
      return -;
    }
    for(;i<n;i++){
      strcat(rheader,"HEAD ");
      strcat(rheader,arr[i]);
      strcat(rheader," HTTP/1.1");
      strcat(rheader,"\r\n");
      strcat(rheader,"Host:");
      strcat(rheader,host->h_name);
      strcat(rheader,"\r\n");

      //strcat(rheader,"Accept:*\/*");
      //strcat(rheader,"\r\n");
      strcat(rheader,"Connection:Keep-Alive");
      strcat(rheader,"\r\n");
      write(sc, rheader, strlen(rheader));usleep();
      bytes = read(sc, resbuf, LINE);
      printf("Response from %s:\n",ip);
      write(STDOUT_FILENO, resbuf, bytes);
      for(i=;i<;i++){
        state[i]=resbuf[i+];
      }
      if(!((state>="" && state<="")||state=="")){
        strcat(manager,"http://");
        strcat(manager,host->h_name);
        strcat(manager,arr[i]);
        strcat(manager,"\r\n");
   write(fd,manager,sizeof(manager));
      }
    }
    close(sc);
    ip = nip(ip);
  }while(strcmp(ip,eip)<);

  close(fd);
  return ;
}