diff options
| -rw-r--r-- | src/pkg/flag/flag.go | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/src/pkg/flag/flag.go b/src/pkg/flag/flag.go index 437aaf230..af221de9b 100644 --- a/src/pkg/flag/flag.go +++ b/src/pkg/flag/flag.go @@ -260,16 +260,11 @@ func PrintDefaults() { }) } -// Usage prints to standard error a default usage message documenting all defined flags and -// then calls os.Exit(1). -func Usage() { - if len(os.Args) > 0 { - fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0]); - } else { - fmt.Fprintln(os.Stderr, "Usage:"); - } +// Usage prints to standard error a default usage message documenting all defined flags. +// The function is a variable that may be changed to point to a custom function. +var Usage = func() { + fmt.Fprintf(os.Stderr, "Usage of %s:\n", os.Args[0]); PrintDefaults(); - os.Exit(1); } func NFlag() int { @@ -415,6 +410,7 @@ func (f *allFlags) parseOne(index int) (ok bool, next int) if len(name) == 0 || name[0] == '-' || name[0] == '=' { print("bad flag syntax: ", s, "\n"); Usage(); + os.Exit(2); } // it's a flag. does it have an argument? @@ -432,18 +428,21 @@ func (f *allFlags) parseOne(index int) (ok bool, next int) if alreadythere { print("flag specified twice: -", name, "\n"); Usage(); + os.Exit(2); } m := flags.formal; flag, alreadythere = m[name]; // BUG if !alreadythere { print("flag provided but not defined: -", name, "\n"); Usage(); + os.Exit(2); } if f, ok := flag.Value.(*boolValue); ok { // special case: doesn't need an arg if has_value { if !f.set(value) { print("invalid boolean value ", value, " for flag: -", name, "\n"); Usage(); + os.Exit(2); } } else { f.set("true") @@ -459,11 +458,13 @@ func (f *allFlags) parseOne(index int) (ok bool, next int) if !has_value { print("flag needs an argument: -", name, "\n"); Usage(); + os.Exit(2); } ok = flag.Value.set(value); if !ok { print("invalid value ", value, " for flag: -", name, "\n"); Usage(); + os.Exit(2); } } flags.actual[name] = flag; |