in the command "pip install -r requirements.txt" what does '-r' meant? same as in "python3 -m pip install something" what does '-m' meant?

Question

I searched before asking this question but i did get exact answer. can anyone let me know where to read about these operators and others like same as this? Thanks in advance.

Answer 1

Run python -h to get a list of arguments and their function.

-m is used to run a library module as a script. In this case you're running pip as a script.

-r is from pip so you can do pip -h for more detail. pip install also has options, so you can do pip install -h for even more detail (you see where this is going). The general idea is -r is meant to install from a requirements file and are treated as dependencies of sorts.

Answer 2

You can use --help to print out the possible set of arguments that a command can take. If you use pip install --help, it will show the arguments and their meaning. See below for the meaning of -r flag:

-r, --requirement <file> Install from the given requirements file. This option can be used multiple times.

Answer 3

-r is used as a way to tell pip to install packages from the requirements file (Usage: pip3 install -r <file>. -r can also be written as --requirement

you can use pip install --help to learn about more arguments you can use with pip install

Answer 4

It means install packages from the given requirements file:

pip install -r <file>
or 
pip install --requirement <file>