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POundefined reference to 'mpg123_open'
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  1. POundefined reference to 'mpg123_open'
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    copied!<p>I am just testing the functionality of the mpg123 library and I am using the code shown below.</p> <pre><code>#include &lt;stdlib.h&gt; #include &lt;unistd.h&gt; #include &lt;stdio.h&gt; #include &lt;fcntl.h&gt; #include &lt;cstring&gt; #include &lt;mpg123.h&gt; #define INBUFF 16384 #define OUTBUFF 32768 void openfile(mpg123_handle* mh , char* filename){ int fnum; int rbytes; int mpg123Status = 0; int channels = 0, encoding = 0; long rate = 0; size_t size; int decodedbytes, decodestatus; int fileSizeSamples; unsigned int framesConsumed; unsigned char *mp3InBuf, *mp3OutBuf; unsigned int mp3InBufSize, mp3OutBufSize; size_t decodedNow; mp3InBufSize = 2048; mp3OutBufSize = 32768; mp3InBuf = new unsigned char[mp3InBufSize]; mp3OutBuf = new unsigned char[mp3InBufSize]; //Open mp3 file for reading fnum = open(filename, O_RDONLY); if(fnum &lt; 0){ printf("ERROR opening file: %s\n", strerror(fnum)); exit(0); } decodedbytes = 0; decodestatus = MPG123_NEED_MORE; mpg123Status = mpg123_init(); if(mpg123Status){ printf("Could not init MPG123: %d - %s\n", mpg123Status, mpg123_plain_strerror(mpg123Status)); close(fnum); exit(0); } mh = mpg123_new(NULL, &amp;mpg123Status); if(mh == NULL){ printf("Could not open mpg123_handle: %d - %s\n", mpg123Status, mpg123_plain_strerror(mpg123Status)); close(fnum); exit(0); } mpg123Status = mpg123_open_feed(mh); if (mpg123Status) { printf( "Could not open mpg123 feed: %d - %s\n", mpg123Status, mpg123_plain_strerror(mpg123Status)); close(fnum); exit(0); } mpg123_open(mh, filename); fileSizeSamples = MPG123_ERR; framesConsumed = 0; /* determine file parameters */ mpg123Status = -1; printf("Start initial decode for file params.\n"); while (MPG123_NEW_FORMAT!=mpg123Status) { /* file -&gt; decoder */ rbytes = read(fnum, mp3InBuf, mp3InBufSize); if (rbytes&gt;0) { mpg123Status = mpg123_decode(mh, mp3InBuf, rbytes, mp3OutBuf, mp3OutBufSize, &amp;size); if ((mpg123Status) &amp;&amp; (MPG123_NEW_FORMAT!=mpg123Status)) { printf("Could not feed mpg123: read %d Bytes %d from file %d - %s\n",size, rbytes, mpg123Status, mpg123_plain_strerror(mpg123Status)); close(fnum); exit(0); } mpg123_getformat(mh, &amp;rate, &amp;channels, &amp;encoding); } } printf("MP3 at %d Hz %d channels %x encoding\n", rate, channels, encoding); /*Read entire file*/ while(!EOF){ rbytes = read(fnum,mp3InBuf,mp3InBufSize); decodestatus = mpg123_decode( mh, mp3InBuf, mp3InBufSize, mp3OutBuf,mp3OutBufSize, &amp;decodedNow); printf("%s",mp3OutBuf); } //Clean up close(fnum); mpg123_close(mh); mpg123_delete(mh); mpg123_exit(); delete [] mp3InBuf; delete [] mp3OutBuf; } int main(int argc, char **argv) { mpg123_handle* mh; //for(;;){ for(int i=1; i&lt;argc; i++){ printf("Opening File: %s\n", argv[i]); openfile(mh, argv[i]); sleep(5); } //} } </code></pre> <p>To compile the above code I am using the following in command in linux:</p> <pre><code>g++ -o mpg123example mpg123example.cpp -lmpg123 </code></pre> <p>And I am getting the following error:</p> <pre><code> In function `openfile(mpg123_handle_struct*, char*)': mpg123example.cpp:(.text+0x196): undefined reference to `mpg123_open' collect2: ld returned 1 exit status </code></pre> <p>My confusion is if the library wan't linked properly why would it not complain about the other function calls? Any suggestions would be appreciated.</p>
 

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