linux编译RTP的问题在网上下载了一个rtp的测试程式。但编译出现问题，不知道怎么回事？ #include stdio.h#i
linux编译RTP的问题
在网上下载了一个rtp的测试程式。但编译出现问题，不知道怎么回事？
#include <stdio.h>
#include <string.h>
#include <iostream>
#include <fstream>
#include <string>
#include <cstdlib>
#include <stdlib.h>
#include "rtpsession.h"
#include "rtppacket.h"
using namespace std;
// 错误处理函数
void checkerror(int err)
{
if (err < 0) {
char* errstr = RTPGetErrorString(err);
printf("Error:%s\\n", errstr);
exit(-1);
}
}
int main(int argc, char** argv)
{
RTPSession sess;
int localport;
int status;
int timestamp,lengh = 1025,length = 0;
char buffer[32768];
unsigned char *RawData;
if (argc != 2) {
printf("Usage: ./recieve localport\\n");
return -1;
}
// 获得用户指定的端口号
localport = atoi(argv[1]);
// 创建RTP会话
status = sess.Create(localport);
checkerror(status);
FILE *file = 0;
int i = 0;
int j = 1;
do {
// 接受RTP数据
status = sess.PollData();
// 检索RTP数据源
if (sess.GotoFirstSourceWithData())
{
do {
RTPPacket* packet;
// 获取RTP数据报
while ((packet = sess.GetNextPacket()) != NULL) {
printf("Got packet %d! of pic %d!\n",i,j);
timestamp = packet->GetTimeStamp();
lengh=packet->GetPayloadLength();
length += lengh;
RawData=packet->GetPayload(); //得到实际有效数据
printf(" timestamp:%d;lengh=%d\n",timestamp,lengh);
memcpy(&buffer[1024*i],RawData,lengh);
i ++;
delete packet;
// 删除RTP数据报
}
} while (sess.GotoNextSourceWithData());
}
if(lengh < 1024)
{
if((file = fopen("rtp_rev.jpg", "wb")) < 0)
{
printf("Unable to create y frame recording file\n");
return -1;
}
else
{
fwrite(buffer, length, 1, file);
printf("buffer write %d bytes into file.\n",length);
fclose(file);
i = 0;//write over so reset i
j ++ ;//write pic and j++
lengh = 1025;
}
}
} while(1);
return 0;
}
编译信息如下：
acer@ubuntu:~/v4l2_jpeg_rtp$ make
sudo g++ -o jpegrtp_reciever jpegrtp_recieve.c -I /home/acer/jrtplib-2.9/share/include/jrtplib/ -L /home/acer/jrtplib-2.9/share/lib/libjrtp.a \
-L /home/acer/jrtplib-2.9/share/lib/libSDL.a -L /home/acer/jrtplib-2.9/share/lib/libSDL_image.a
/tmp/ccEbgatJ.o: In function `checkerror(int)':
jpegrtp_recieve.c:(.text+0x13): undefined reference to `RTPGetErrorString(int)'
/tmp/ccEbgatJ.o: In function `main':
jpegrtp_recieve.c:(.text+0x67): undefined reference to `RTPSession::RTPSession()'
jpegrtp_recieve.c:(.text+0xc4): undefined reference to `RTPSession::Create(int, unsigned long)'
jpegrtp_recieve.c:(.text+0xfb): undefined reference to `RTPSession::PollData()'
jpegrtp_recieve.c:(.text+0x1c7): undefined reference to `RTPPacket::~RTPPacket()'
jpegrtp_recieve.c:(.text+0x2b2): undefined reference to `RTPSession::~RTPSession()'
jpegrtp_recieve.c:(.text+0x2ca): undefined reference to `RTPSession::~RTPSession()'
/tmp/ccEbgatJ.o: In function `RTPSession::GotoFirstSourceWithData()':
jpegrtp_recieve.c:(.text._ZN10RTPSession23GotoFirstSourceWithDataEv[RTPSession::GotoFirstSourceWithData()]+0x2a): undefined reference to `RTPSources::GotoFirstSourceWithData()'
/tmp/ccEbgatJ.o: In function `RTPSession::GotoNextSourceWithData()':
jpegrtp_recieve.c:(.text._ZN10RTPSession22GotoNextSourceWithDataEv[RTPSession::GotoNextSourceWithData()]+0x2a): undefined reference to `RTPSources::GotoNextSourceWithData()'
/tmp/ccEbgatJ.o: In function `RTPSession::GetNextPacket()':
jpegrtp_recieve.c:(.text._ZN10RTPSession13GetNextPacketEv[RTPSession::GetNextPacket()]+0x4a): undefined reference to `RTPSourceData::ExtractPacket()'
collect2: ld returned 1 exit status
make: *** [all] 错误 1
[解决办法]-L只是指定路径，还需要-l
这样：
-L /home/acer/jrtplib-2.9/share/lib/ -l jrtp \
-L /home/acer/jrtplib-2.9/share/lib -l SDL -L /home/acer/jrtplib-2.9/share/lib/ -l SDL_image
