Handling stdin in Go

Internal

• Go Code Examples
• Go Strings
• fmt Package

Handling stdin with fmt Functions

When used to read strings, fmt.Scan* functions seem to want to tokenize the string and store fragments into different variables.

fmt.Scan()

https://golang.org/pkg/fmt/#Scan

Read text from stdin. It stores successive space-separated values into successive arguments. Newlines count as space. It returns the number of items successfully scanned. If that is less than the number of arguments, err will report why.

var s string
cnt, err := fmt.Scan(&s)
fmt.Printf("input line: %s, cnt: %d, error: %s\n", s, cnt, err)

fmt.Scanln()

https://golang.org/pkg/fmt/#Scanln

Scanln is similar to Scan, but stops scanning at a newline or EOF. It still uses space as separator, and stores space-separated fragments into successive arguments.

var line string
fmt.Scanln(&line)

fmt.Scanf()

https://golang.org/pkg/fmt/#Scanf

var f float
cnt, err := fmt.Scanf("%f", &f)