docker - Using ARG and ENV in Dockerfile - Stack Overflow At least since 20 10 2, ARGs can be passed from outside the FROM line onwards, all you need to do is insert another ARG with the same name after the FROM: ARG my_arg ARG other_arg=other_default FROM centos:7 # These need to be re-stated here to use the ARGs above
python - Use of *args and **kwargs - Stack Overflow print required_arg # args is a tuple of positional arguments, # because the parameter name has * prepended if args: # If args is not empty print args # kwargs is a dictionary of keyword arguments, # because the parameter name has ** prepended
dockerfile - How do I set environment variables during the docker . . . ARG is only available during the build of a Docker image (RUN etc), not after the image is created and containers are started from it (ENTRYPOINT, CMD) ENV values are available to containers, but also RUN-style commands during the Docker build starting with the line where they are introduced
c++ - What does int argc, char *argv [] mean? - Stack Overflow The variables are named argc (argument count) and argv (argument vector) by convention, but they can be given any valid identifier: int main(int num_args, char** arg_strings) is equally valid They can also be omitted entirely, yielding int main(), if you do not intend to process command line arguments Try the following program:
docker - How to pass arguments to a Dockerfile? - Stack Overflow As of Docker 1 9, You are looking for --build-arg and the ARG instruction Check out this document for reference This will allow you to add ARG arg to the Dockerfile and then build with docker build --build-arg arg=2 3
What does ** (double star asterisk) and * (star asterisk) do for . . . a is a required argument, and its value is 100 b not required, its default value is 10, actual value: 2 args is of type <type 'tuple'> and length 0 kwargs is of type <type 'dict'> and length 4 unknown kwarg - kw: c, arg: 3 unknown kwarg - kw: e, arg: 5 unknown kwarg - kw: d, arg: 4 unknown kwarg - kw: f, arg: 6 Args or kwargs can be passed