Module io

Description
Data Types
Function Index
Function Details

An implementation of the Erlang/OTP io interface.

Description

This module implements a strict subset of the Erlang/OTP io interface.

Data Types

device()


device() = atom() | pid() | standard_io() | standard_error() | user()

format()


format() = atom() | string() | binary()

getopt()


getopt() = {echo, boolean()} | {binary, boolean()} | {encoding, unicode} | {terminal, boolean()} | {stdin, boolean()} | {stdout, boolean()} | {stderr, boolean()}

standard_error()


standard_error() = standard_error

standard_io()


standard_io() = standard_io

user()


user() = user

Function Index

columns/0	Returns the number of columns for standard I/O.
columns/1	Returns the number of columns for passed I/O device.
format/1	Equivalent to `fwrite(Format)`.
format/2	Equivalent to `fwrite(Format, Data)`.
format/3	Equivalent to `fwrite(IODevice, Format, Data)`.
fwrite/1	Equivalent to `fwrite(Format, [])`.
fwrite/2	Equivalent to `fwrite(standard_io, Format, Data)`.
fwrite/3	Format string and data to IO device.
get_line/1	Read string from console with prompt.
getopts/0	Get all options for standard I/O.
getopts/1	Get all options for a given IODevice.
printable_range/0	Returns the user-requested range of printable Unicode characters.
put_chars/1	Writes the given character(s) to the console.
put_chars/2	Writes the given character(s) to the given device.
requests/1
scan_erl_exprs/4	Reads data from IODevice with a given prompt.

Function Details

columns/0


columns() -> {ok, pos_integer()} | {error, enotsup}

Equivalent to columns(standard_io).

Returns the number of columns for standard I/O.

columns/1


columns(IODevice::device()) -> {ok, pos_integer()} | {error, enotsup}

IODevice: IO device to get columns of

Returns the number of columns for passed I/O device.

format/1


format(Format::format()) -> ok

Equivalent to fwrite(Format).

format/2


format(Format::format(), Data::[term()]) -> ok

Equivalent to fwrite(Format, Data).

format/3


format(IODevice::device(), Format::format(), Data::[term()]) -> ok

Equivalent to fwrite(IODevice, Format, Data).

fwrite/1


fwrite(Format::format()) -> ok

Equivalent to fwrite(Format, []).

fwrite/2


fwrite(Format::format(), Data::[term()]) -> ok

Equivalent to fwrite(standard_io, Format, Data).

fwrite/3


fwrite(IODevice::device(), Format::string(), Args::list()) -> string()

IODevice: device to write to
Format: format string

returns: ok

Format string and data to IO device. See io_lib:format/2 for information about formatting capabilities.

get_line/1


get_line(Prompt::string()) -> string()

Prompt: prompt for user input

returns: string

Read string from console with prompt.

getopts/0


getopts() -> [getopt()] | {error, Reason::any()}

Equivalent to getopts(standard_io).

Get all options for standard I/O

getopts/1


getopts(IODevice::device()) -> [getopt()] | {error, Reason::any()}

IODevice: IO device to get options for

Get all options for a given IODevice

printable_range/0


printable_range() -> unicode | latin1

Returns the user-requested range of printable Unicode characters. Currently always returns unicode

put_chars/1


put_chars(Chars::list() | binary()) -> ok

Chars: character(s) to write to console

returns: ok

Equivalent to put_chars(standard_io, Chars).

Writes the given character(s) to the console.

put_chars/2


put_chars(Device::device(), Chars::list() | binary()) -> ok

Device: device to send characters to
Chars: character(s) to write to device

returns: ok

Writes the given character(s) to the given device.

requests/1

requests(Requests) -> any()

scan_erl_exprs/4


scan_erl_exprs(IODevice::device(), Prompt::atom() | unicode:chardata(), StartLocation::any(), Options::any()) -> {ok, Tokens::any(), EndLocation::any()} | {eof, EndLocation::any()} | eof | {error, any()}

IODevice: device to read from
Prompt: prompt to print
StartLocation: start location for reading
Options: options for tokenizing

returns: read tokens or an error

Reads data from IODevice with a given prompt