/usr/share/doc/radare2/gdb is in radare2 0.9.6-3.1+deb8u1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 | Connecting r2 with gdb
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Running gdbserver
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$ gdbserver :2345 /bin/ls
(gdb) target remote localhost:2345
Connecting from r2
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$Write failed: Host is down5
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