Sentry Answers>Go>

How To Convert a Zero-Terminated Byte Array to a String in Go

How To Convert a Zero-Terminated Byte Array to a String in Go

Venter C.

The Problem

When working with C libraries or system calls in Go, you encounter a zero-terminated byte array.

The Solution

A zero-terminated byte array is a sequence of bytes that end with a null byte (0x00). This is a common way to represent strings in C, using a null byte to mark the end of a string.

You can use the bytes.IndexByte function to find the position of the null byte, then use the string type conversion to convert the byte array to a string.

Consider the following example:

Click to Copy
package main import ( "bytes" "fmt" ) func ZeroTerminatedToString(byteArray []byte) string { nullIndex := bytes.IndexByte(byteArray, 0) // Find the first occurrence of the null byte (\x00) if nullIndex == -1 { return string(byteArray) // No null terminator found, convert entire slice } return string(byteArray[:nullIndex]) // Slice up to the null terminator } func main() { // Example byte array with a zero-terminator byteArray := []byte{'H', 'e', 'l', 'l', 'o', 0, 'W', 'o', 'r', 'l', 'd'} str := ZeroTerminatedToString(byteArray) fmt.Println(str) }

This returns the following output:

Click to Copy
Hello

This approach ensures that only the first part of the byte array, up to the first zero byte, is considered. If your input is guaranteed to have a null terminator, this function will safely extract the intended string.

Further reading

  • SentryGo Error Tracking and Performance Monitoring
  • Syntax.fmListen to the Syntax Podcast
  • Syntax.fm logo
    Listen to the Syntax Podcast

    Tasty treats for web developers brought to you by Sentry. Get tips and tricks from Wes Bos and Scott Tolinski.

    SEE EPISODES

Considered “not bad” by 4 million developers and more than 100,000 organizations worldwide, Sentry provides code-level observability to many of the world’s best-known companies like Disney, Peloton, Cloudflare, Eventbrite, Slack, Supercell, and Rockstar Games. Each month we process billions of exceptions from the most popular products on the internet.

© 2024 • Sentry is a registered Trademark of Functional Software, Inc.