Package fileutil implements utility functions related to files and paths.



    View Source
    const (
    	// PrivateFileMode grants owner to read/write a file.
    	PrivateFileMode = 0600
    	// PrivateDirMode grants owner to make/remove files inside the directory.
    	PrivateDirMode = 0700
    View Source
    const (
    	F_OFD_GETLK  = 37
    	F_OFD_SETLK  = 37
    	F_OFD_SETLKW = 38

      This used to call syscall.Flock() but that call fails with EBADF on NFS. An alternative is lockf() which works on NFS but that call lets a process lock the same file twice. Instead, use Linux's non-standard open file descriptor locks which will block if the process already holds the file lock.

      constants from /usr/include/bits/fcntl-linux.h


      View Source
      var (
      	ErrLocked = errors.New("fileutil: file already locked")


      func CreateDirAll

      func CreateDirAll(dir string) error

        CreateDirAll is similar to TouchDirAll but returns error if the deepest directory was not empty.

        func Exist

        func Exist(name string) bool

        func Fdatasync

        func Fdatasync(f *os.File) error

          Fdatasync is similar to fsync(), but does not flush modified metadata unless that metadata is needed in order to allow a subsequent data retrieval to be correctly handled.

          func Fsync

          func Fsync(f *os.File) error

            Fsync is a wrapper around file.Sync(). Special handling is needed on darwin platform.

            func IsDirWriteable

            func IsDirWriteable(dir string) error

              IsDirWriteable checks if dir is writable by writing and removing a file to dir. It returns nil if dir is writable.

              func OpenDir

              func OpenDir(path string) (*os.File, error)

                OpenDir opens a directory for syncing.

                func Preallocate

                func Preallocate(f *os.File, sizeInBytes int64, extendFile bool) error

                  Preallocate tries to allocate the space for given file. This operation is only supported on linux by a few filesystems (btrfs, ext4, etc.). If the operation is unsupported, no error will be returned. Otherwise, the error encountered will be returned.

                  func PurgeFile

                  func PurgeFile(dirname string, suffix string, max uint, interval time.Duration, stop <-chan struct{}) <-chan error

                  func ReadDir

                  func ReadDir(dirpath string) ([]string, error)

                    ReadDir returns the filenames in the given directory in sorted order.

                    func TouchDirAll

                    func TouchDirAll(dir string) error

                      TouchDirAll is similar to os.MkdirAll. It creates directories with 0700 permission if any directory does not exists. TouchDirAll also ensures the given directory is writable.

                      func ZeroToEnd

                      func ZeroToEnd(f *os.File) error

                        ZeroToEnd zeros a file starting from SEEK_CUR to its SEEK_END. May temporarily shorten the length of the file.


                        type LockedFile

                        type LockedFile struct{ *os.File }

                        func LockFile

                        func LockFile(path string, flag int, perm os.FileMode) (*LockedFile, error)

                        func TryLockFile

                        func TryLockFile(path string, flag int, perm os.FileMode) (*LockedFile, error)