What do you know about the runtime package? What methods have you used?

The runtime package in Go provides functions for interacting with the language's runtime, including goroutine management, garbage collection, system information, and debugging.

Key features and methods commonly used:

• runtime.GOOS and runtime.GOARCH — constants indicating the operating system and architecture.

• runtime.NumGoroutine() — returns the current number of goroutines.

• runtime.GOMAXPROCS(n int) — sets the maximum number of OS threads that can execute Go code simultaneously.

• runtime.Caller(skip int) — returns information about the caller in the call stack (file, line, function), useful for logging and debugging.

• runtime.Stack(buf []byte, all bool) — records the stack trace into a buffer, used for diagnostics.

• runtime.GC() — forcibly runs the garbage collector.

Example of using runtime.NumGoroutine:

package main

import (
    "fmt"
    "runtime"
)

func main() {
    fmt.Println("Goroutines before start:", runtime.NumGoroutine())

    go func() {
        // some work
    }()

    fmt.Println("Goroutines after start:", runtime.NumGoroutine())
}

Thus, the runtime package is useful for monitoring and controlling program behavior at a low level.