io

Members

(static) POLLERR :number

Source:
Default Value:
  • 8
Type:
  • number

(static) POLLHUP :number

Source:
Default Value:
  • 16
Type:
  • number

(static) POLLIN :number

Source:
Default Value:
  • 1
Type:
  • number

(static) POLLMSG :number

Source:
Default Value:
  • 1024
Type:
  • number

(static) POLLNVAL :number

Source:
Default Value:
  • 32
Type:
  • number

(static) POLLOUT :number

Source:
Default Value:
  • 4
Type:
  • number

(static) POLLPRI :number

Source:
Default Value:
  • 2
Type:
  • number

(static) POLLRDBAND :number

Source:
Default Value:
  • 128
Type:
  • number

(static) POLLRDHUP :number

Source:
Default Value:
  • 8192
Type:
  • number

(static) POLLRDNORM :number

Source:
Default Value:
  • 64
Type:
  • number

(static) POLLREMOVE :number

Source:
Default Value:
  • 4096
Type:
  • number

(static) POLLWRBAND :number

Source:
Default Value:
  • 512
Type:
  • number

(static) POLLWRNORM :number

Source:
Default Value:
  • 256
Type:
  • number

(static) SEEK_CUR :number

Source:
Default Value:
  • 1

Seek from current position

Type:
  • number

(static) SEEK_END :number

Source:
Default Value:
  • 2

Seek from end of file

Type:
  • number

(static) SEEK_SET :number

Source:

Seek from start of file

Type:
  • number

Methods

(static) append(pathname, modeopt) → {number}

Source:
See:

Open a file for appending. If the file does not exist it is created. If it exists its contents remain untouched.

Note that the file pointer will always be set to EOF before any write operation.

Note that the file is always open in write only mode.

Parameters:
Name Type Attributes Default Description
pathname string

Path to file
mode number <optional>
 0644

File mode bits of file in case it needs to be created
Throws:
SysError
Returns:

The file descriptor

Type
number

(static) close(fd, fail_if_closedopt) → {0}

Source:

Close an open file

Parameters:
Name Type Attributes Default Description
fd number

The file descriptor
fail_if_closed boolean <optional>
 true

Fail if file is already closed
Throws:
SysError
Returns:
Type
0

(static) create(pathname, modeopt, accessopt) → {number}

Source:
See:

Open a file. If the file does not exist it is created. If it exists its contents remain untouched.

Parameters:
Name Type Attributes Default Description
pathname string

Path to file
mode number <optional>
 0644

File mode bits of file in case it needs to be created
access string <optional>
 'rw'

Access mode of file ('r', 'w', or 'rw')
Throws:
SysError
Returns:

The file descriptor

Type
number

(static) dup(fd) → {number}

Source:

Duplicate an open file descriptor

Parameters:
Name Type Description
fd number

The existing file descriptor
Throws:
SysError
Returns:

The new file descriptor

Type
number

(static) dup2(openFd, changedFd) → {number}

Source:

Duplicate an open file descriptor assigning it to another custom fd

Parameters:
Name Type Description
openFd number

The existing file descriptor
changedFd number

The file descriptor that will be changed
Throws:
SysError
Returns:

The changed file descriptor

Type
number

(static) open(pathname, accessopt) → {number}

Source:
See:

Open an existing file.

Parameters:
Name Type Attributes Default Description
pathname string

Path to file
access string <optional>
 'rw'

Access mode ('r', 'w', or 'rw')
Throws:
SysError
Returns:

The file descriptor

Type
number

(static) pipe() → {Array.<number>}

Source:

Create a pipe

Throws:
SysError
Returns:

An array with two file descriptors where [0] item is the read end of the pipe and [1] is the write end.

Type
Array.<number>

(static) poll(fds, timeoutopt) → {number}

Source:

The poll() function provides applications with a mechanism for multiplexing input/output over a set of file descriptors.

For each member of the array pointed to by fds, poll() shall examine the given file descriptor for the event(s) specified in events.

The poll() function shall identify those file descriptors on which an application can read or write data, or on which certain events have occurred.

Parameters:
Name Type Attributes Default Description
fds Pollfd

File descriptors and events to check
timeout number <optional>
 -1

Timeout in milliseconds or -1 to wait forever
Throws:
SysError
Returns:

Count of fds with events or 0 on timeout

Type
number

(static) read(fd, buf, countopt) → {number}

Source:

Read bytes from an open file

Parameters:
Name Type Attributes Default Description
fd number

An open file desriptor
buf Uint8Array

Buffer to fill with read bytes
count number <optional>
 -1

Maximum number of bytes to read, or -1 to read until buffer is full or EOF.

Note that it is not the same -1 as buf.length, because buf.length does not guarantee that the whole buffer is read.
Throws:
SysError
Returns:

The number of bytes read (with 0 meaning end of file).

In the case where count = -1, a return less than buffer length means that EOF was reached.

Type
number

(static) read_fully(fd) → {Uint8Array}

Source:

Read contents of a fd until it is exhausted and return them as an Uint8Array.

Parameters:
Name Type Description
fd number

An open file desriptor
Throws:
SysError
Returns:

The bytes contained by the file

Type
Uint8Array

(static) read_string(fd) → {string}

Source:

Read contents of a fd until it is exhausted and return them as a string.

The bytes are interpreted as UTF-8.

Parameters:
Name Type Description
fd number

An open file desriptor
Throws:
SysError
Returns:

The contents of the file interpreted as an UTF-8 string

Type
string

(static) seek(fd, offset, whence) → {number}

Source:

Set the pointer of a file descriptor to a given value

Parameters:
Name Type Description
fd number

An open file descriptor
offset number

Relative offset for file pointer
whence number

Base of offset. One of the values: module:io.SEEK_SET, module:io.SEEK_CUR, or module:io.SEEK_END.
Throws:
SysError
Returns:

The resulting offset measured from start of file

Type
number

(static) tell(fd) → {number}

Source:

Retrieve the current offset of the file pointer from the start of the file.

Parameters:
Name Type Description
fd number

An open file desriptor
Throws:
SysError
Returns:

The offset of the file pointer

Type
number

(static) truncate(pathname, modeopt, accessopt) → {number}

Source:
See:

Open a file and empty it. If the file does not exist it is created.

Parameters:
Name Type Attributes Default Description
pathname string

Path to file
mode number <optional>
 0644

File mode bits of file in case it needs to be created
access string <optional>
 'rw'

Access mode of file ('r', 'w', or 'rw')
Throws:
SysError
Returns:

The file descriptor

Type
number

(static) write(fd, buf, countopt) → {number}

Source:

Write bytes to an open file

Parameters:
Name Type Attributes Default Description
fd number

An open file desriptor
buf Uint8Array

Buffer containing bytes to write
count number <optional>
 -1

Maximum number of bytes to write or -1 to keep writing until all buffer has been written.

Note that it is not the same -1 as buf.length, because buf.length does not guarantee that the whole buffer is written.
Throws:
SysError
Returns:

The number of bytes written

Type
number

(static) write_string(fd, str) → {number}

Source:

Write a string as UTF-8 bytes to an open file

Parameters:
Name Type Description
fd number

An open file desriptor
str string

The string to write
Throws:
SysError
Returns:

The number of bytes written

Type
number