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Module CCIO

module CCIO: sig .. end

IO Utils

Simple utilities to deal with basic Input/Output tasks in a resource-safe way. For advanced IO tasks, the user is advised to use something like Lwt or Async, that are far more comprehensive.

Examples: 

# let l = CCIO.(with_in "/tmp/some_file" read_lines);;



# CCIO.(

  with_in "/tmp/input"

    (fun ic ->

      let chunks = read_chunks ic in

      with_out ~flags:[Open_binary] ~mode:0o644 "/tmp/output"

        (fun oc ->

          write_gen oc chunks

        )

    )

) ;;

Before 0.12 was in 'containers.io', now moved into 'containers'
Since 0.6
type 'a gen = unit -> 'a option
See Gen in the gen library

Input


val with_in : ?mode:int ->
       ?flags:Pervasives.open_flag list ->
       string -> (Pervasives.in_channel -> 'a) -> 'a
Open an input file with the given optional flag list, calls the function on the input channel. When the function raises or returns, the channel is closed.
flags : opening flags (default [Open_text]). Open_rdonly is used in any cases
val read_chunks : ?size:int -> Pervasives.in_channel -> string gen
Read the channel's content into chunks of size size
val read_line : Pervasives.in_channel -> string option
Read a line from the channel. Returns None if the input is terminated. The "\n" is removed from the line.
val read_lines : Pervasives.in_channel -> string gen
Read all lines. The generator should be traversed only once.
val read_lines_l : Pervasives.in_channel -> string list
Read all lines into a list
val read_all : ?size:int -> Pervasives.in_channel -> string
Read the whole channel into a buffer, then converted into a string.
Since 0.7
size : the internal buffer size
val read_all_bytes : ?size:int -> Pervasives.in_channel -> Bytes.t
Read the whole channel into a mutable byte array
Since 0.12
size : the internal buffer size

Output


val with_out : ?mode:int ->
       ?flags:Pervasives.open_flag list ->
       string -> (Pervasives.out_channel -> 'a) -> 'a
Same as CCIO.with_in but for an output channel
flags : opening flags (default [Open_creat; Open_trunc; Open_text]). Open_wronly is used in any cases
val with_out_a : ?mode:int ->
       ?flags:Pervasives.open_flag list ->
       string -> (Pervasives.out_channel -> 'a) -> 'a
Similar to CCIO.with_out but with the [Open_append; Open_creat; Open_wronly] flags activated, to append to the file
val write_line : Pervasives.out_channel -> string -> unit
Write the given string on the channel, followed by "\n"
val write_gen : ?sep:string -> Pervasives.out_channel -> string gen -> unit
Write the given strings on the output. If provided, add sep between every two strings (but not at the end)
val write_lines : Pervasives.out_channel -> string gen -> unit
Write every string on the output, followed by "\n".
val write_lines_l : Pervasives.out_channel -> string list -> unit

Both


val with_in_out : ?mode:int ->
       ?flags:Pervasives.open_flag list ->
       string -> (Pervasives.in_channel -> Pervasives.out_channel -> 'a) -> 'a
Combines CCIO.with_in and CCIO.with_out.
Since 0.12
flags : opening flags (default [Open_creat])

Misc for Generators


val tee : ('a -> unit) list -> 'a gen -> 'a gen
tee funs gen behaves like gen, but each element is given to every function f in funs at the time the element is produced.

File and file names

How to list recursively files in a directory: 

# let files = CCIO.File.read_dir ~recurse:true (CCIO.File.make "/tmp");;

# CCIO.write_lines stdout files;;

See CCIO.File.walk if you also need to list directories: 

# let content = CCIO.File.walk (CCIO.File.make "/tmp");;

# Gen.map CCIO.File.show_walk_item content |> CCIO.write_lines stdout;;



module File: sig .. end