从另一个程序运行一个程序

Question

I have a C# program(call it A) that takes a photo and transforms it in a 2d array of values. I also have a c++(call it B) program that use as input that type of matrix. What I want to do is to call A by code written in B. I have no idea how to specify input for A (don't know if it's possible in any way). The only solution I found is to have a directory in which I have the photo(s) and a file that first is opened written in and closed by A when it is called and than B open it again and read it. The question is: Is there a way to give input to a program called from another program?

Answer 1

The simplest way to do it is by using a pipeline. In terminal it would look like this:

programA < image | programB

Answer 2

There are many ways to pass input from one program to another.

• Write a file in one program and read it in another.

• Create a shared memory region and store the data there (use for example boost::shared_memory , or shm_open on Posix, or CreateFileMapping on Windows.

• Write the data to stdout in one program, read from stdin in the other and pipe the two programs together.

• Create a pipe and write the data to one end of the pipe, and read from the other end.
• Have one program listen on a socket, and the other send data to it.
• More

Depending on usage, all of these can be appropriate, but I would stick to writing a file to start with. It makes it much easier to separately test and debug the two programs. Rather than using a fixed directory and filename, I would have A write to a file, and then invoke B with the name of the file on the command line.