[winswitch] What do I need to set PKG_CONFIG_PATH to in order to build XPRA?

[Timothy Hobbs]

I'm trying to build the latest subversion version of XPRA on Debian 
strech (in Docker), and it fails saying PKG_CONFIG_PATH is empty. What 
should I set this ENV_VAR to?

Thanks

timothy at b8610ea160fd5a04a294:/pwd/src$ ./setup.py install --home=install
./setup.py install --home=install
Xpra version 2.0
found pkg-config version: 0.29
build switches:
* enc_x264             : Y
* enc_x265             : N
* enc_ffmpeg           : Y
* nvenc7               : N
* vpx                  : Y
* pillow               : Y
* v4l2                 : Y
* dec_avcodec2         : Y
* csc_swscale          : Y
* csc_libyuv           : N
* bencode              : Y
* cython_bencode       : Y
* vsock                : Y
* mdns                 : Y
* clipboard            : Y
* server               : Y
* client               : Y
* dbus                 : Y
* x11                  : Y
* gtk_x11              : Y
* service              : Y
* gtk2                 : Y
* gtk3                 : N
* html5                : Y
* minify               : Y
* pam                  : N
* sound                : Y
* opengl               : Y
* printing             : Y
* webcam               : Y
* rebuild              : Y
* annotate             : Y
* warn                 : Y
* strict               : Y
* shadow               : Y
* proxy                : Y
* debug                : N
* PIC                  : Y
* Xdummy               : Auto
* Xdummy_wrapper       : Auto
* verbose              : N
* tests                : N
* bundle_tests         : N
error running (['uglifyjs', '--version'],),{'stderr': -1, 'stdout': -1}: 
[Errno 2] No such file or directory
Warning: uglifyjs failed and return -1
Warning: yuicompressor module not found, cannot minify
'nvcc --version' failed with return code 127
stderr: None
updated ./xpra/build_info.py with:
* BUILD_BIT            = 64bit
* BUILD_CPU            = Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz
* BUILD_DATE           = 2016-12-31
* BUILD_MACHINE        = x86_64
* BUILD_OS             = Linux debian stretch/sid
* BUILD_TIME           = 00:44
* BUILT_BY             = timothy
* BUILT_ON             = b8610ea160fd5a04a294
* COMPILER_VERSION     = gcc (Debian 6.2.1-5) 6.2.1 20161124
* CYTHON_VERSION       = 0.25.2b0
* LINKER_VERSION       = GNU ld (GNU Binutils for Debian) 2.27.51.20161201
* PYTHON_VERSION       = 2.7.13
* RELEASE_BUILD        = True
* lib_pygobject        = 2.28.6
* lib_pygtk            = 2.24.0
* lib_vpx              = 1.6.0
* lib_x11              = 1.6.4
* lib_x264             = 0.148.2728 4d5c8b0
* lib_xcomposite       = 0.4.4
* lib_xdamage          = 1.1.4
* lib_xext             = 1.3.3
* lib_xfixes           = 5.0.3
* lib_xkbfile          = 1.0.9
* lib_xrandr           = 1.5.1
* lib_xtst             = 1.2.3
found gcc version: 6.2.1
Traceback (most recent call last):
   File "./setup.py", line 2367, in <module>
     ffmpeg_pkgconfig = pkgconfig("libavcodec", "libavformat")
   File "./setup.py", line 663, in exec_pkgconfig
     raise Exception("ERROR: cannot find a valid pkg-config entry for %s 
using PKG_CONFIG_PATH=%s" % (" or ".join(options), 
os.environ.get("PKG_CONFIG_PATH", "(empty)")))
Exception: ERROR: cannot find a valid pkg-config entry for libavformat 
using PKG_CONFIG_PATH=(empty)