Fix #219: (OSX) free() structure only if necessary
Fix #219: (OSX) free() structure only if necessary

jucapj/psutil,google-code-export/psutil,marmolu/psutil,end18/psutil,creativewild/psutil,stupidcache/psutil,nmani1905/psutil,huson2012/psutil,peter-hst/psutil,kiranvizru/psutil,creativewild/psutil,tigerneil/psutil,Alwnikrotikz/psutil,PFZheng/psutil,kiranvizru/psutil,huson2012/psutil,huson2012/psutil,djhaskin987/psutil,anfedorov/psutil,chjwang/psutil,kiranvizru/psutil,tigerneil/psutil,skyshe/psutil,zhengzheng/psutil,google-code-export/psutil,google-code-export/psutil,PFZheng/psutil,google-code-export/psutil,tigerneil/psutil,marmolu/psutil,jucapj/psutil,end18/psutil,skyshe/psutil,vmolsa/psutil,end18/psutil,stupidcache/psutil,stupidcache/psutil,end18/psutil,creativewild/psutil,Alwnikrotikz/psutil,anfedorov/psutil,tigerneil/psutil,vmolsa/psutil,vmolsa/psutil,shiva21/psutil,kiranvizru/psutil,chjwang/psutil,nmani1905/psutil,djhaskin987/psutil,vmolsa/psutil,AlanZatarain/psutil,djhaskin987/psutil,shiva21/psutil,skyshe/psutil,peter-hst/psutil,AlanZatarain/psutil,zhengzheng/psutil,skyshe/psutil,djhaskin987/psutil