I can't dynamically link to libvlc.dylib on macOS, while on Windows it works great

[alex3333]

Hello,

I have very simple code that loads libvlc at runtime and plays an mp4 file:

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void* load_fn(char* func) { void *res=dlsym(vlc_lib, func); if (!res) exit(1); return res; } int main() { char* path = "/Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib"; // libvlc.dll on Windows vlc_lib = dlopen(path, RTLD_LAZY); if (!vlc_lib) { printf("dl not loaded: %s\n", path); exit(1); } _libvlc_new=load_fn("libvlc_new"); _libvlc_media_new_location=load_fn("libvlc_media_new_location"); // a couple of other necessary functions are loaded // ..... vlc = _libvlc_new(0, 0); libvlc_media_t *m = _libvlc_media_new_path (vlc, "video.mp4"); mp = _libvlc_media_player_new_from_media (m); _libvlc_media_release (m); _libvlc_media_player_set_nsobject (mp, ns_video_view); // on Windows I call set_hwnd() _libvlc_media_player_play (mp); }

On Windows it works like a charm. But on macOS I get a crash in libvlc_media_player_new_from_media:

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* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x28) frame #0: 0x000000010d610a7d libvlccore.dylib`config_GetPsz + 61 libvlccore.dylib`config_GetPsz: -> 0x10d610a7d <+61>: mov rdi, qword ptr [rbx + 0x28] 0x10d610a81 <+65>: test rdi, rdi 0x10d610a84 <+68>: je 0x10d610a90 ; <+80> 0x10d610a86 <+70>: call 0x10d6998a8 ; symbol stub for: strdup (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x28) * frame #0: 0x000000010d610a7d libvlccore.dylib`config_GetPsz + 61 frame #1: 0x000000010d67d3c7 libvlccore.dylib`var_Inherit + 247 frame #2: 0x000000010d67d232 libvlccore.dylib`var_Create + 354 frame #3: 0x000000010d4d727c libvlc.dylib`libvlc_media_player_new + 316 frame #4: 0x000000010d4d7be0 libvlc.dylib`libvlc_media_player_new_from_media + 16

I tried the latest stable release and the most recent git build.

I had to modify the library file because of macOS @rpath shenanigans:

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install_name_tool -change @rpath/libvlccore.dylib /Applications/VLC.app/Contents/MacOS/lib/libvlccore.dylib /Applications/VLC.app/Contents/MacOS/lib/libvlc.dylib

otherwise it wouldn't load at all.

Does any one have experience with linking to libvlc.dylib?

Thanks a lot

[Jean-Baptiste Kempf]

That's currently expected with macOS @rpath mess.

Use VLCKit or find a way to modify the rpath so it works in both VLC and linking to it (and share it with us )

[mfkl]

Related https://github.com/xamarin/xamarin-macios/issues/4416, might give you some insight.

Good luck