How to Use Main Arguments in C++
Hi there, my name is Muzaffer Arda Uslu. I am a computer engineering student at Eskişehir Osmangazi University.
This article I’m gonna show how can we use main function’s arguments in C++.
Firstly, let’s learn ‘argc’.
argc contains the number of arguments passed to the program and also it is short way for “argument count”. Every C++ program has one argument at least. Then this argument is our .exe file.
So, what is ‘argv’?
argv is the name of the variable argv stands for “argument vector”. A vector is a one-dimensional array and argv is a one-dimensional array of strings.
I’m gonna show an example program.
Create a C++ project and let’s put a name “bohemian-rhapsody” for project and our .exe file’s name will be “bohemian-rhapsody.exe”. In this way, our argv array’s first index is “bohemian-rhapsody.exe”.
We have two .txt files. They are “read.txt.” and “write.txt”.
read.txt:
“write.txt” is empty.
The program reads “read.txt” file and writes what it reads to the “write.txt”.
We set the three files from cmd for this program.
Go to bohemian-rhapsody.exe’s folder in file explorer.
X:\….\repos\bohemian-rhapsody\Debug
Click to path and type “cmd” then press enter.
We have three argument. They are “bohemian-rhapsody.exe”, “read.txt” and “write.txt”.
Find in order this files with TAB key and press enter. After pressing the program starts.
Here is the program’s code:
