问题
(I am on Ubuntu) I am trying to run the PortAudio examples, but getting many errors (mentioned below). I have placed the header file portaudio.h in the directory of the program. I have no idea about it. I think it is linker error. Please help!
/tmp/cc5EbTlT.o: In function main':
paex_record.c:(.text+0x37e): undefined reference toPa_Initialize'
paex_record.c:(.text+0x397): undefined reference to Pa_GetDefaultInputDevice'
paex_record.c:(.text+0x3de): undefined reference toPa_GetDeviceInfo'
paex_record.c:(.text+0x436): undefined reference to Pa_OpenStream'
paex_record.c:(.text+0x45a): undefined reference toPa_StartStream'
paex_record.c:(.text+0x493): undefined reference to Pa_Sleep'
paex_record.c:(.text+0x4c2): undefined reference toPa_IsStreamActive'
paex_record.c:(.text+0x4eb): undefined reference to Pa_CloseStream'
paex_record.c:(.text+0x5fa): undefined reference toPa_GetDefaultOutputDevice'
paex_record.c:(.text+0x641): undefined reference to Pa_GetDeviceInfo'
paex_record.c:(.text+0x6b2): undefined reference toPa_OpenStream'
paex_record.c:(.text+0x6e3): undefined reference to Pa_StartStream'
paex_record.c:(.text+0x71c): undefined reference toPa_Sleep'
paex_record.c:(.text+0x728): undefined reference to Pa_IsStreamActive'
paex_record.c:(.text+0x74e): undefined reference toPa_CloseStream'
paex_record.c:(.text+0x77d): undefined reference to Pa_Terminate'
paex_record.c:(.text+0x7e5): undefined reference toPa_GetErrorText'
collect2: error: ld returned 1 exit status
回答1:
Assuming you are compiling using gcc and you have a single C file foo.c, the compiler command would be
gcc -o foo foo.c -lrt -lasound -ljack -lpthread -lportaudio
The -l parameters are there to link the required libraries to your program, e.g. -lrt will link librt.a. The order does matter.
I got the required libraries from here: http://www.portaudio.com/docs/v19-doxydocs/compile_linux.html#comp_linux3. Don't know if they are correct. At least you need -lportaudio, obviously.
If the libraries are not found, you have to provide gcc a path, e.g.
gcc -L/usr/lib -o foo foo.c -lrt -lasound -ljack -lpthread -lportaudio
Regarding the header, you don't actually need to copy it into your program's directory. You'd rather include it as
#include <portaudio.h>
and add its directory to the include search path:
gcc -I/usr/include -L/usr/lib -o foo foo.c -lrt -lasound -ljack -lpthread -lportaudio
Of course, all this is better done in a Makefile.
来源：https://stackoverflow.com/questions/32972796/error-while-compiling-portaudio-examples