My machine is a Mac with OS X El Capitan installed.Using Homebrew I have installed openssl 1.0.2h_1 but it does not allow it to be linked to usr/local.openssl version -a returns:OpenSSL 0.9.8zh 14 Jan 2016 built on: Feb 4 2016 platform: darwin64-x86_64-llvm options: bn(64,64) md2(int) rc4(ptr,char) des(idx,cisc,16,int) blowfish(idx) compiler: -arch x86_64 -fmessage-length=0 -pipe -Wno-trigraphs -fpascal-strings -fasm-blocks -O3 -D_REENTRANT -DDSO_DLFCN -DHAVE_DLFCN_H -DL_ENDIAN -DMD32_REG_T=int -DOPENSSL_NO_IDEA -DOPENSSL_PIC -DOPENSSL_THREADS -DZLIB -mmacosx-version-min=10.6 OPENSSLDIR: "/System/Library/OpenSSL"which openssl returns /usr/bin/openssl.I want to build Boost but I understand from the answer posted to this question that Boost will use the openssl version provided by the system.How do I force the boost build to use the version of openssl I have installed via Homebrew?