简单实现了传输的功能，基本没有错误和异常处理……

服务器端
<br></br>#include <stdio.h><br></br>#include <stdlib.h><br></br>#include <string.h><br></br>#include <strings.h><br></br>#include <sys><br></br>#include <sys><br></br>#include <netdb.h><br></br>#include <fcntl.h></fcntl.h></netdb.h></sys></sys></strings.h></string.h></stdlib.h></stdio.h>

#define DEBUG 1

#define OPCODE_RRQ (1)
#define OPCODE_WRQ (2)
#define OPCODE_DATA (3)
#define OPCODE_ACK (4)
#define OPCODE_ERR (5)

#define BLOCKSIZE (512)

struct TFTPHeader{
short opcode;
}__attribute__((packed));

struct TFTPWRRQ{
struct TFTPHeader header;
char *filename; // Terminal as \0x00
char *mode; // Terminal as \0x00
}__attribute__((packed));

struct TFTPData{
struct TFTPHeader header;
short block;
void* data;
}__attribute__((packed));

struct TFTPACK{
struct TFTPHeader header;
short block;
}__attribute__((packed));