Use Different PHP version During Composer Install or Update

Use following command to specify PHP version.

php7.2 /usr/bin/composer install

OR

php7.2 /usr/bin/composer update

/usr/bin/php7.2 /usr/bin/composer install

OR

/usr/bin/php7.2 /usr/bin/composer update

If you get any error like Could not open input file: composer, then composer excitable location is incorrect. To find exact location use the following command 

which composer

To know php7.2 location use the follwing command

which php7.2