32 lines
646 B
Go
32 lines
646 B
Go
|
// The flock package provides a file-system mediated locking mechanism on linux
|
||
|
|
// using the `flock` system call.
|
||
|
|
|
||
|
|
package flock
|
||
|
|
|
||
|
|
import (
|
||
|
|
"os"
|
||
|
|
"syscall"
|
||
|
|
)
|
||
|
|
|
||
|
|
|
||
|
|
// Lock gets an exclusive lock on the file at the given path. If the file
|
||
|
|
// doesn't exist, it's created.
|
||
|
|
func Lock(path string) (*os.File, error) {
|
||
|
|
perm := os.O_CREATE | os.O_RDWR
|
||
|
|
fh, err := os.OpenFile(path, perm, 0600)
|
||
|
|
if err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
if err := syscall.Flock(int(fh.Fd()), syscall.LOCK_EX); err != nil {
|
||
|
|
return nil, err
|
||
|
|
}
|
||
|
|
|
||
|
|
return fh, nil
|
||
|
|
}
|
||
|
|
|
||
|
|
// Unlock releases the lock acquired via the Lock function.
|
||
|
|
func Unlock(f *os.File) error {
|
||
|
|
return f.Close()
|
||
|
|
}
|