Usage:
nc -l -p 61916
AITESTPLUGIN=1 LL_WRAPPER='gdb --args' ./singularity
Then paste into nc:
<llsd>
<map>
<key>class</key>
<string>internal</string>
<key>name</key>
<string>load_plugin</string>
<key>params</key>
<map>
<key>dir</key>
<string>/opt/secondlife/viewers/singularity/SingularityViewer/linden/indra/viewer-linux-x86_64-debug/newview/packaged/bin/llplugin</string>
<key>file</key>
<string>/opt/secondlife/viewers/singularity/SingularityViewer/linden/indra/viewer-linux-x86_64-debug/newview/packaged/bin/llplugin/libbasic_plugin_filepicker.so</string>
</map>
</map>
</llsd>
and press control-v control-shift-2
Where the path should match the library you want to load.