hello

Print "Hello, world!"

$ hello

$ hello [[-t|--traditional]]

$ hello [[-g|--greeting]] "[greeting_text]"

hello

The `hello` command is a basic, often custom-built, executable used primarily in educational contexts or as a very simple example. It demonstrates the fundamental concept of executing a program on a Linux system.

Because it is not a standard part of most distributions, its implementation and location are highly variable. Typically, a `hello` command would be a compiled program written in languages like C or Python. Its function is straightforward: upon execution, it prints the word "hello" (or potentially "Hello, World!") to the standard output.

This command serves as a starting point for learning about compiling source code, setting environment variables, and understanding the basic input/output operations within a Linux environment. It's a valuable tool for confirming that the toolchain works on a clean system. It is often not present on a system unless manually created. The exact source code and behavior can vary greatly between systems.

The `hello` command's existence and behavior are not guaranteed across different Linux distributions. It's a custom command, so its presence depends entirely on whether a user or administrator has created it.

If a `hello` executable exists, running it from the command line would simply print 'hello' (or similar text) to the terminal.
Example:
$ hello
hello

A simple C implementation might look like this:
#include
int main() {
printf("hello\n");
return 0;
}
This code would be compiled using a C compiler such as GCC.