/usr/bin/php vs /bin/php vs php in bash [closed]

Question

We are running a php client command. php xx yy zz run just fine but not its counter parts (/usr/bin/php and /bin/php) which give very weird error.

I am so confused row, given that :

command -v php || which php || type -p php 

=> /usr/bin/php (( all 3 of them)

whereis php 

=> php: /usr/bin/php /usr/bin/php7.3 /usr/lib/php /etc/php /usr/include/php /usr/share/php /usr/share/php7.3-xmlrpc /usr/share/php7.3-imap /usr/share/php7.3-opcache /usr/share/php7.3-zip /usr/share/php7.3-curl /usr/share/php7.3-common /usr/share/php7.3-bcmath /usr/share/php7.3-soap /usr/share/php7.2-xml /usr/share/php7.3-gd /usr/share/php7.3-mysql /usr/share/php7.3-mbstring /usr/share/php7.2-common /usr/share/php7.3-json /usr/share/php7.3-xml /usr/share/php7.3-readline /usr/share/man/man1/php.1.gz

type -a php 

=> php is /usr/bin/php

php is /bin/php

Why my script works with "php" but /usr/bin/php or /bin/php. What are the different between them ?

Answer 1

Basically, there are two ways php is installed on your lets say Linux system. For apache use for webserver. And for cli use.

You can check the web version using <?php phpinfo(); ?> function for a web page.

For cli you can check path and version using which php and php --version respactivitly.

Difference php-cgi and php-cli

PHP CLI is the command-line interface for PHP (e.g. for creating standalone applications) PHP CGI is the common gateway interface for PHP (e.g. for web applications) Source: https://stackoverflow.com/a/9315749/2107145

You might want to read this thread https://stackoverflow.com/a/45493656/2107145 for details of all php version.

Explaination of commands

type: will display information about command

which: will display binary path of given command

command: display information about command

whereis: will find all binaries of given command say php

thats all for now.

Ask me if you need to know more.