Build libcurl for iOS 6.0. Modified Bob's script on Stackoverflow for iOS 6.0.

build_libcurl_ios.sh

#!/bin/sh 
export SDK=6.0

buildit()
{
    target=$1
    platform=$2

    export CC=/Applications/Xcode.app/Contents/Developer/Platforms/${platform}.platform/Developer/usr/bin/gcc
    export CFLAGS="-arch ${target} -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/${platform}.platform/Developer/SDKs/${platform}${SDK}.sdk"
    export CPP="/Applications/Xcode.app/Contents/Developer/Platforms/${platform}.platform/Developer/usr/bin/llvm-cpp-4.2"
    export AR=/Applications/Xcode.app/Contents/Developer/Platforms/${platform}.platform/Developer/usr/bin/ar
    export RANLIB=/Applications/Xcode.app/Contents/Developer/Platforms/${platform}.platform/Developer/usr/bin/ranlib

    ./configure --disable-shared --without-ssl --without-libssh2 --without-ca-bundle --without-ldap --disable-ldap \
            --host=${target}-apple-darwin10

    make clean
    make
    $AR rv libcurl.${target}.a lib/*.o
}

buildit armv7 iPhoneOS
buildit armv7s iPhoneOS
buildit i386 iPhoneSimulator

lipo -create libcurl.armv7.a libcurl.armv7s.a libcurl.i386.a -output libcurl.a