package uwt

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include module type of Fs_types with type uv_open_flag = Fs_types.uv_open_flag with type file_kind = Fs_types.file_kind with type symlink_mode = Fs_types.symlink_mode with type access_permission = Fs_types.access_permission with type stats = Fs_types.stats
type uv_open_flag = Fs_types.uv_open_flag =
  1. | O_RDONLY
    (*

    Open for reading

    *)
  2. | O_WRONLY
    (*

    Open for writing

    *)
  3. | O_RDWR
    (*

    Open for reading and writing

    *)
  4. | O_NONBLOCK
    (*

    Open in non-blocking mode, ignored on Windows

    *)
  5. | O_CREAT
    (*

    Create if nonexistent

    *)
  6. | O_EXCL
    (*

    Fail if existing

    *)
  7. | O_TRUNC
    (*

    Truncate to 0 length if existing

    *)
  8. | O_APPEND
    (*

    Open for append

    *)
  9. | O_NOCTTY
    (*

    Don't make this dev a controlling tty, ignored on Windows

    *)
  10. | O_DSYNC
    (*

    Writes complete as `Synchronised I/O data integrity completion', ignored by some platforms

    *)
  11. | O_SYNC
    (*

    Writes complete as `Synchronised I/O file integrity completion', ignored by some platforms

    *)
  12. | O_RSYNC
    (*

    Reads complete as writes (depending on O_SYNC/O_DSYNC), only supported on some Unix platforms, ignored otherwise

    *)
  13. | O_TEMPORARY
    (*

    windows only, ignored on Unix

    *)
  14. | O_SHORT_LIVED
    (*

    windows only, ignored on Unix

    *)
  15. | O_SEQUENTIAL
    (*

    windows only, ignored on Unix

    *)
  16. | O_RANDOM
    (*

    windows only, ignored on Unix

    *)
  17. | O_DIRECT
    (*

    On Windows supported since libuv 1.16

    *)
  18. | O_EXLOCK
    (*

    OS X (and Windows, but with different semantic)

    *)
  19. | O_NOATIME
    (*

    no windows, some Unix systems, ignored otherwise

    *)
  20. | O_NOFOLLOW
    (*

    no windows, some Unix systems, ignored otherwise

    *)
  21. | O_DIRECTORY
    (*

    no windows, some Unix systems, ignored otherwise

    *)

Flags for Fs_functions.openfile

O_CLOEXEC doesn't exist, because this flag is unconditionally added by libuv. O_SHARE_DELETE, O_SHARE_WRITE, O_SHARE_READ are always added on Windows, unless O_EXLOCK is specified.

type file_kind = Fs_types.file_kind =
  1. | S_REG
    (*

    Regular file

    *)
  2. | S_DIR
    (*

    Directory

    *)
  3. | S_CHR
    (*

    Character device

    *)
  4. | S_BLK
    (*

    Block device

    *)
  5. | S_LNK
    (*

    Symbolic link

    *)
  6. | S_FIFO
    (*

    Named pipe

    *)
  7. | S_SOCK
    (*

    Socket

    *)
  8. | S_UNKNOWN
    (*

    Everything else - possible on some platforms.

    *)

On Windows it can be specified how to create symlinks.

type access_permission = Fs_types.access_permission =
  1. | Read
    (*

    Read permission

    *)
  2. | Write
    (*

    Write permission

    *)
  3. | Exec
    (*

    Execution permission

    *)
  4. | Exists
    (*

    File exists

    *)
type stats = Fs_types.stats = {
  1. st_dev : int;
    (*

    Device number

    *)
  2. st_kind : file_kind;
    (*

    Kind of the file

    *)
  3. st_perm : int;
    (*

    Access rights

    *)
  4. st_uid : int;
    (*

    User id of the owner

    *)
  5. st_gid : int;
    (*

    Group ID of the file's group

    *)
  6. st_rdev : int;
    (*

    Device minor number

    *)
  7. st_ino : int;
    (*

    Inode number

    *)
  8. st_size : int64;
    (*

    Size in bytes

    *)
  9. st_blksize : int;
    (*

    "Preferred" block size for efficient filesystem I/O

    *)
  10. st_blocks : int;
    (*

    Number of blocks allocated to the file, in 512-byte units

    *)
  11. st_flags : int;
    (*

    User defined flags for file

    *)
  12. st_gen : int;
    (*

    File generation number

    *)
  13. st_atime : int64;
    (*

    Last access time

    *)
  14. st_atime_nsec : int;
    (*

    Nanosecond components of last access time

    *)
  15. st_mtime : int64;
    (*

    Last modification time

    *)
  16. st_mtime_nsec : int;
    (*

    Nanosecond components of last modification time

    *)
  17. st_ctime : int64;
    (*

    Last status change time

    *)
  18. st_ctime_nsec : int;
    (*

    Nanosecond components of lastt status change time

    *)
  19. st_birthtime : int64;
    (*

    File creation time

    *)
  20. st_birthtime_nsec : int;
    (*

    Nanosecond components of File creation time

    *)
}

File status information. Support for the various fields differs depending on the OS and filesystem.

type clone_mode =
  1. | No_clone
    (*

    Create a normal copy

    *)
  2. | Try_clone
    (*

    Try to clone the file, but create a normal copy, if it fails

    *)
  3. | Force_clone
    (*

    Try tlone the file, don't create a normal copy, if it fails

    *)

Clone mode for Fs_functions.copyfile

type 'a t
val openfile : ?perm:int -> mode:uv_open_flag list -> string -> file t

Equivalent to open(2).

  • parameter perm

    defaults are 0o644

val read : ?pos:int -> ?len:int -> file -> buf:bytes -> int t

read ~pos ~len fd ~buf reads ~len bytes from descriptor fd, storing them in byte sequence buf, starting at position ~pos in ~buf. Return the number of bytes actually read.

  • parameter pos

    default is always zero

  • parameter len

    default is always the still available length of the string / bigarray / Bytes.t

val read_ba : ?pos:int -> ?len:int -> file -> buf:buf -> int t

like read, buf for bigarrays. Bigarrays are passed directly to libuv (no copy to c heap or stack). It's faster, but you must manually ensure, that the bigarray is not accessed from another thread.

val pread : ?pos:int -> ?len:int -> file -> fd_offset:int64 -> buf:bytes -> int t

pread is equivalent to read, except that it reads from a given position ~fd_offset in the file without changing the file offset.

val pread_ba : ?pos:int -> ?len:int -> file -> fd_offset:int64 -> buf:buf -> int t
val write : ?pos:int -> ?len:int -> file -> buf:bytes -> int t

write fd ~pos ~len fd ~buf writes ~len bytes to descriptor fd, taking them from byte sequence buf, starting at position ~pos in ~buf. Return the number of bytes actually written.

val write_string : ?pos:int -> ?len:int -> file -> buf:string -> int t
val write_ba : ?pos:int -> ?len:int -> file -> buf:buf -> int t
val pwrite : ?pos:int -> ?len:int -> file -> fd_offset:int64 -> buf:bytes -> int t

pwrite is equivalent to write, except that it writes into a given position ~fd_offset and does not change the file offset

val pwrite_string : ?pos:int -> ?len:int -> file -> fd_offset:int64 -> buf:string -> int t
val pwrite_ba : ?pos:int -> ?len:int -> file -> fd_offset:int64 -> buf:buf -> int t
val writev : file -> Iovec_write.t list -> int t

write multiple buffers at once. If the number of buffers is greater than IOV_MAX, newer libuv versions already contains code to circumvent this issue

val pwritev : file -> Iovec_write.t list -> int64 -> int t

pwritev is equivalent to pwrite, except that it writes into a given position and does not change the file offset

val close : file -> unit t

Close a file descriptor.

delete a name and possibly the file it refers to

val mkdir : ?perm:int -> string -> unit t

Create a directory.

  • parameter perm

    defaults are 0o777

val rmdir : string -> unit t

Delete an empty directory

val fsync : file -> unit t

synchronize a file's in-core state with storage device.

val fdatasync : file -> unit t

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.

val ftruncate : file -> len:int64 -> unit t

truncate a file to a specified length

val stat : string -> stats t

Return the information for the named file.

val lstat : string -> stats t

lstat is identical to stat, except that if pathname is a symbolic link. In this case it returns information about the link itself.

val fstat : file -> stats t

fstat is identical to stat, except that the file about which information is to be retrieved is specified by the file descriptor

val rename : src:string -> dst:string -> unit t

change the name or location of a file

link creates a new link (also known as a hard link) to an existing file

symlink creates a symbolic link named ~dst which contains the string ~src

  • parameter mode

    default S_Default

val mkdtemp : string -> string t

The mkdtemp function generates a uniquely named temporary directory from template. The last six characters of template must be XXXXXX and these are replaced with a string that makes the directory name unique

val sendfile : ?pos:int64 -> ?len:nativeint -> dst:file -> src:file -> unit -> nativeint t

A limited equivalent to sendfile(2). It copies data between one file descriptor and another

  • parameter pos

    default 0

  • parameter len

    default: SIZE_MAX

val utime : string -> access:float -> modif:float -> unit t

utime changes the access and modification times of a file. If both times are 0.0, the access and last modification times are both set to the current time.

val futime : file -> access:float -> modif:float -> unit t

futime is identical to utime, except that the file about which information is to be retrieved is specified by the file descriptor

readlink reads the value of a symbolic link

val access : string -> access_permission list -> unit t

Check user's permissions for a file

val chmod : string -> perm:int -> unit t

Change the permissions of the named file.

val fchmod : file -> perm:int -> unit t

Change the permissions of an opened file.

val chown : string -> uid:int -> gid:int -> unit t

Change the owner ~uid and owner ~gid of the named file.

val fchown : file -> uid:int -> gid:int -> unit t

Change the owner ~uid and owner ~gid of the opened file.

val lchown : string -> uid:int -> gid:int -> unit t

like chown, but do not dereference symbolic links

val scandir : string -> (file_kind * string) array t

On Linux, getting the type of an entry is only supported by some filesystems (btrfs, ext2, ext3 and ext4 at the time of this writing), check the getdents(2) man page.

val realpath : string -> string t

Equivalent to realpath(3) on Unix. Windows uses GetFinalPathNameByHandle.

Warning This function has certain platform specific caveats that were discovered when used in Node.

macOS and other BSDs: this function will fail with UV_ELOOP if more than 32 symlinks are found while resolving the given path. This limit is hardcoded and cannot be sidestepped.

Windows: while this function works in the common case, there are a number of corner cases where it doesn't:

  • Paths in ramdisk
  • volumes created by tools which sidestep the Volume Manager (such as ImDisk) cannot be resolved.
  • Inconsistent casing when using drive letters.
  • Resolved path bypasses subst'd drives.

While this function can still be used, it's not recommended if scenarios such as the above need to be supported.

val copyfile : ?excl:bool -> ?clone:clone_mode -> src:string -> dst:string -> unit -> unit t

Copies a file from ~src to ~dst.

If ?excl is true, copyfile will fail with EEXIST if the destination path already exists. The default behavior is to overwrite the destination if it exists.

If ?clone is Try_clone, copyfile will attempt to create a copy-on-write reflink. If the underlying platform (or your installed libuv version) does not support copy-on-write, then a fallback copy mechanism is used. If ?clone is Force_clone, copyfile will attempt to create a copy-on-write reflink. If the underlying platform does not support copy-on-write, then an error is returned. The default behaviour is a normal copy (No_clone).

Warning: If the destination path is created, but an error occurs while copying the data, then the destination path is removed. There is a brief window of time between closing and removing the file where another process could access the file.