You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: passphrase.go
    path of file: ./repos/podman/vendor/github.com/containers/image/v5/pkg/cli
    
    the code of the file until where you have to start completion: package cli

import (
	"bufio"
	"errors"
	"fmt"
	"io"
	"os"
	"strings"

	"github.com/sirupsen/logrus"
)

// ReadPassphraseFile returns the first line of the specified path.
// For convenience, an empty string is returned if the path is 
    
func ReadPassphraseFile(path string) (string, error) {
	if path == "" {
		return "", nil
	}

	logrus.Debugf("Reading user-specified passphrase for signing from %s", path)

	ppf, err := os.Open(path)
	if err != nil {
		return "", err
	}
	defer ppf.Close()

	// Read the *first* line in the passphrase file, just as gpg(1) does.
	buf, err := bufio.NewReader(ppf).ReadBytes('\n')
	if err != nil && !errors.Is(err, io.EOF) {
		return "", fmt.Errorf("reading passphrase file: %w", err)
	}

	return strings.TrimSuffix(string(buf), "\n"), nil
}