In C programming, the term “command line” usually refers to a method by which users can interact with programs or the operating system via textual commands.

When it comes to C, this could refer to two related but different things:

  1. Command-Line Arguments:
    C programs can accept command-line arguments, which are parameters passed to the program when it is started from the command line. The signature of the main() function in a C program can be set up to accept these arguments, like so: int main(int argc, char *argv[]) { // ... } Here, argc is the argument count, and argv is an array of argument values. This is a standard way in C to handle command-line arguments.
  2. Command-Line Compilation:
    C programs are typically compiled from the command line using a compiler like GCC (GNU Compiler Collection). Here’s an example of how you might compile a C program from the command line: gcc -o my_program my_program.c In this command:
    • gcc is the compiler,-o my_program specifies the output file name for the compiled program,my_program.c is the source file being compiled.
    Other flags and options can be specified on the command line to control the compilation process, like -Wall to enable all compiler warnings, or -g to include debugging information in the output.

These two aspects of “command lines” in C demonstrate the language’s close relationship with the underlying system and its flexibility in being controlled and manipulated via textual commands.