This is the answer to "How to install sqlserver driver for php71 on OSX?".

1. Install pear && pecl

curl -O http://pear.php.net/go-pear.phar  
sudo php -d detect_unicode=0 go-pear.phar

• type 1, return, enter "/usr/local/pear"
• type 4 , return, enter "/usr/local/bin"
• return

check pear with:

pear version

2. Install pear && pecl

sudo pecl install sqlsrv pdo_sqlsrv 
sudo echo "extension=pdo_sqlsrv.so" >> `php --ini | grep "Loaded Configuration" | sed -e "s|.*:\s*||"`
sudo echo "extension=sqlsrv.so" >> `php --ini | grep "Loaded Configuration" | sed -e "s|.*:\s*||"`

3. Install OBDC

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
brew tap microsoft/mssql-release https://github.com/Microsoft/homebrew-mssql-release
brew update
brew install --no-sandbox msodbcsql mssql-tools

if error: odbcinst: SQLRemoveDriver failed with Unable to find component name.

check:

1.) whether the file odbcinst.ini is existed under the folder /usr/local/Cellar/unixodbc/2.3.4/etc/

2.) if it exists, list out the contents of this file: cat /usr/local/Cellar/unixodbc/2.3.4/etc/odbcinst.ini

3.) list out the permission of the file: ls -l /usr/local/Cellar/unixodbc/2.3.4/etc

4.) check if you can see the error 'odbcinst: SQLRemoveDriver failed with General installer error' by running the command in a terminal window: odbcinst -u -d -n "ODBC Driver 13 for SQL Server"

5.) see if you can run the command successfully if you prefix the command with sudo in the terminal window: sudo odbcinst -u -d -n "ODBC Driver 13 for SQL Server"

6.) if it runs without the error, brew doesn't have write permission for the file odbcinst.ini. It shouldn't need sudo to modify the file.