The difference between print and fmt.Print

First declare, in Go language:

• exists print, printlndoes not existprintf
• exist fmt.Println, fmt.Printlnwithfmt.Printf

The following are the specific differences between printand fmt.Print:

	print	fmt.Print
source	Go's built-in functions, no need to import packages	The functions in the fmt package need to import the fmt package
Formatting ability	does not support formatted output	Support complex formatted output
Suggested usage scenarios	Mainly used for debugging, not recommended for production environment	Recommended for production environment
return value	no return value	Returns the number of bytes printed and possible errors
print complex objects	just print out the address	Print out the details of the object

Case: Use fmt.Printlnthe return value to verify whether an error occurs in the print statement:

func main() {
    
    
	n, err := fmt.Println("Hello, world!")
  
	if err != nil {
    
    
		fmt.Fprintf(os.Stderr, "Println failed: %v\n", err)
		os.Exit(1)
	}
  
	fmt.Println("Printed", n, "bytes")
}

In this example, we print "Hello, world!"and then check for fmt.Printlnerrors returned. If an error occurs, we write the error message to os.Stderrand exit the program. If no errors occurred, we print out the number of bytes written.

In most cases, fmt.Println will not return an error. But if you os.Stdoutredirect to a closed or unwritable file, or similar problems, fmt.Println may return an error.