A Go program for replacing spaces in filenames with underscores.

nospace.go

package main

// Using filenames or filename patters (using glob symbols), find filenames
// with spaces in the names and replace the spaces with underscores.

import (
    "log"
    "os"
    "path"
    "path/filepath"
    "strings"
)

func main() {
    args := os.Args[1:]
    if len(args) == 0 {
        log.Fatalf("No files passed.\n")
    }
    for _, arg := range args {
        files, err := filepath.Glob(arg)
        if err != nil {
            log.Fatal(err)
        }
        if len(files) == 0 {
            log.Printf("No files found matching %s.\n", arg)
            continue
        }
        for _, file := range files {
            base := path.Base(file)
            if strings.Index(base, " ") == -1 {
                continue
            }
            new := path.Join(path.Dir(file), strings.Replace(base, " ", "_", -1))
            _, err := os.Stat(new)
            if err == nil {
                log.Printf("Not renaming %s; %s already exists.\n", file, new)
                continue
            }
            err = os.Rename(file, new)
            if err != nil {
                log.Fatal(err)
            }
        }
    }

}