diff options
Diffstat (limited to 'src/os/exec/exec.go')
| -rw-r--r-- | src/os/exec/exec.go | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/src/os/exec/exec.go b/src/os/exec/exec.go index e84ebfc453..e0c509cbef 100644 --- a/src/os/exec/exec.go +++ b/src/os/exec/exec.go @@ -102,6 +102,7 @@ import ( "runtime" "strconv" "strings" + "sync/atomic" "syscall" "time" ) @@ -354,6 +355,9 @@ type Cmd struct { // the work of resolving the extension, so Start doesn't need to do it again. // This is only used on Windows. cachedLookExtensions struct{ in, out string } + + // startCalled records that Start was attempted, regardless of outcome. + startCalled atomic.Bool } // A ctxResult reports the result of watching the Context associated with a @@ -635,7 +639,8 @@ func (c *Cmd) Run() error { func (c *Cmd) Start() error { // Check for doubled Start calls before we defer failure cleanup. If the prior // call to Start succeeded, we don't want to spuriously close its pipes. - if c.Process != nil { + // It is an error to call Start twice even if the first call did not create a process. + if c.startCalled.Swap(true) { return errors.New("exec: already started") } @@ -647,6 +652,7 @@ func (c *Cmd) Start() error { if !started { closeDescriptors(c.parentIOPipes) c.parentIOPipes = nil + c.goroutine = nil // aid GC, finalization of pipe fds } }() |