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FILE (interface)​

An object representing a file handle.

declare interface FILE {
  target: string | number;
  close(): void;
  puts(...strings: Array<string>): void;
  printf(fmt: string, ...args: Array<any>): void;
  flush(): void;
  sync(): void;
  seek(offset: number | bigint, whence: number): void;
  tell(): number;
  tello(): bigint;
  eof(): boolean;
  fileno(): number;
  read(buffer: ArrayBuffer, position: number, length: number): number;
  write(buffer: ArrayBuffer, position: number, length: number): number;
  writeTo(target: FILE, bufferSize: number, limit?: number): number;
  getline(): string | null;
  readAsString(maxSize?: number): string;
  getByte(): number;
  putByte(value: number): void;
  setvbuf(mode: number, size: number): void;
}

FILE.target (property)​

Human-readable description of where this FILE points.

If target is a number, the FILE was opened with fdopen, and target is the fd. Otherwise, target will be an arbitrary string that describes the file; it may be the absolute path to the file, the relative path to the file at time of its opening, or some other string like "stdin" or "tmpfile".

You should not use this property for anything other than logging and debugging. It is only provided for debugging and/or troubleshooting purposes. The value of this property could change at any time when upgrading QuickJS or yavascript, even if upgrading by a minor or patch release.

target: string | number;

FILE.close (method)​

Close the file handle. Note that for files other than stdin/stdout/stderr, the file will be closed automatically when the FILE object is garbage-collected.

close(): void;

FILE.puts (method)​

Outputs the string with the UTF-8 encoding.

puts(...strings: Array<string>): void;

FILE.printf (method)​

Formatted printf.

The same formats as the standard C library printf are supported. Integer format types (e.g. %d) truncate the Numbers or BigInts to 32 bits. Use the l modifier (e.g. %ld) to truncate to 64 bits.

printf(fmt: string, ...args: Array<any>): void;

FILE.flush (method)​

Flush the buffered file. Wrapper for C fflush.

flush(): void;

FILE.sync (method)​

Sync the buffered file to disk. Wrapper for C fsync.

sync(): void;

FILE.seek (method)​

Seek to a given file position (whence is std.SEEK_*).

offset can be a number or a bigint.

seek(offset: number | bigint, whence: number): void;

FILE.tell (method)​

Return the current file position.

tell(): number;

FILE.tello (method)​

Return the current file position as a bigint.

tello(): bigint;

FILE.eof (method)​

Return true if end of file.

eof(): boolean;

FILE.fileno (method)​

Return the associated OS handle.

fileno(): number;

FILE.read (method)​

Read length bytes from the file to the ArrayBuffer buffer at byte position position (wrapper to the libc fread). Returns the number of bytes read, or 0 if the end of the file has been reached.

read(buffer: ArrayBuffer, position: number, length: number): number;

FILE.write (method)​

Write length bytes from the ArrayBuffer buffer at byte position position into the file (wrapper to the libc fwrite). Returns the number of bytes written.

write(buffer: ArrayBuffer, position: number, length: number): number;

FILE.writeTo (method)​

Write this file into target, using a memory buffer of size bufferSize.

If limit is specified, only that amount of bytes will be read and written. Otherwise, data is read and written until this file reaches EOF.

A limit of 0 is treated the same as not specifying a limit.

Internally, this function uses libc fread and fwrite in a loop.

Returns the number of bytes read and written.

writeTo(target: FILE, bufferSize: number, limit?: number): number;

FILE.getline (method)​

Return the next line from the file, assuming UTF-8 encoding, excluding the trailing line feed or EOF.

If the end of the file has been reached, then null will be returned instead of a string.

Note: Although the trailing line feed has been removed, a carriage return (\r) may still be present.

getline(): string | null;

FILE.readAsString (method)​

Read maxSize bytes from the file and return them as a string assuming UTF-8 encoding. If maxSize is not present, the file is read up its end.

readAsString(maxSize?: number): string;

FILE.getByte (method)​

Return the next byte from the file. Return -1 if the end of file is reached.

getByte(): number;

FILE.putByte (method)​

Write one byte to the file.

putByte(value: number): void;

FILE.setvbuf (method)​

Set the buffering mode and buffer size for the file stream (wrapper to the libc setvbuf()).

Note that unlike the libc setvbuf, the "buffer" argument is not supported, and therefore is not present.

  • @param mode — The buffering mode to use. It can be one of the following values: std._IOFBF for full buffering, std._IOLBF for line buffering, or std._IONBF for no buffering.
  • @param size — The size to resize the internal in-memory buffer for this file to.
setvbuf(mode: number, size: number): void;

"quickjs:std" (namespace)​

declare module "quickjs:std" {
  export function loadFile(filename: string): string;
  export function isFILE(value: any): boolean;
  export function open(filename: string, flags: string): FILE;
  export function popen(command: string, flags: string): FILE;
  export function fdopen(fd: number, flags: string): FILE;
  export function tmpfile(): FILE;
  export function puts(...strings: Array<string>): void;
  export function printf(fmt: string, ...args: Array<any>): void;
  export function sprintf(fmt: string, ...args: Array<any>): void;
  var in_: FILE;
  export { in_ as in };
  export var out: FILE;
  export var err: FILE;
  export var SEEK_SET: number;
  export var SEEK_CUR: number;
  export var SEEK_END: number;
  export var _IOFBF: number;
  export var _IOLBF: number;
  export var _IONBF: number;
  export var BUFSIZ: number;
  export function getenv(name: string): string | undefined;
  export function setenv(name: string, value: string): void;
  export function unsetenv(name: string): void;
  export function getenviron(): {
    [key: string]: string | undefined;
  };
  export function getuid(): number;
  export function geteuid(): number;
  export function getgid(): number;
  export function getegid(): number;
  export interface PasswdEntry {
    name: string;
    passwd: string;
    uid: number;
    gid: number;
    gecos: string;
    dir: string;
    shell: string;
  }
  export function getpwuid(id: number): PasswdEntry;
  interface UrlGet {
    (url: string): string;
    (
      url: string,
      options: {
        binary: false;
      },
    ): string;
    (
      url: string,
      options: {
        full: false;
      },
    ): string;
    (
      url: string,
      options: {
        binary: false;
        full: false;
      },
    ): string;
    (
      url: string,
      options: {
        binary: true;
      },
    ): ArrayBuffer;
    (
      url: string,
      options: {
        binary: true;
        full: false;
      },
    ): ArrayBuffer;
    (
      url: string,
      options: {
        full: true;
      },
    ): {
      status: number;
      response: string;
      responseHeaders: string;
    };
    (
      url: string,
      options: {
        full: true;
        binary: false;
      },
    ): {
      status: number;
      response: string;
      responseHeaders: string;
    };
    (
      url: string,
      options: {
        full: true;
        binary: true;
      },
    ): {
      status: number;
      response: ArrayBuffer;
      responseHeaders: string;
    };
  }
  export var urlGet: UrlGet;
  export function parseExtJSON(str: string): any;
  export function strftime(
    maxBytes: number,
    format: string,
    time: Date | number,
  ): string;
}

"quickjs:std".loadFile (exported function)​

Load the file filename and return it as a string assuming UTF-8 encoding.

  • @param filename — The relative or absolute path to the file to load. Relative paths are resolved relative to the process's current working directory.
export function loadFile(filename: string): string;

"quickjs:std".isFILE (exported function)​

Return a boolean indicating whether the provided value is a FILE object.

  • @param value — The value to check.
  • @returns Whether the value was a FILE or not.
export function isFILE(value: any): boolean;

"quickjs:std".open (exported function)​

Open a file (wrapper to the libc fopen()). Return the FILE object.

  • @param filename — The relative or absolute path to the file to open. Relative paths are resolved relative to the process's current working directory.
  • @param flags — A string containing any combination of the characters 'r', 'w', 'a', '+', and/or 'b'.
  • @returns The opened FILE object.
export function open(filename: string, flags: string): FILE;

"quickjs:std".popen (exported function)​

Open a process by creating a pipe (wrapper to the libc popen()). Return the FILE object.

  • @param command — The command line to execute. Gets passed via /bin/sh -c.
  • @param flags — A string containing any combination of the characters 'r', 'w', 'a', '+', and/or 'b'.
  • @returns The opened FILE object.
export function popen(command: string, flags: string): FILE;

"quickjs:std".fdopen (exported function)​

Open a file from a file handle (wrapper to the libc fdopen()). Return the FILE object.

  • @param fd — The file handle to open.
  • @param flags — A string containing any combination of the characters 'r', 'w', 'a', '+', and/or 'b'.
  • @returns The opened FILE object.
export function fdopen(fd: number, flags: string): FILE;

"quickjs:std".tmpfile (exported function)​

Open a temporary file. Return the FILE object.

  • @returns The opened FILE object.
export function tmpfile(): FILE;

"quickjs:std".puts (exported function)​

Equivalent to std.out.puts(str).

export function puts(...strings: Array<string>): void;

"quickjs:std".printf (exported function)​

Equivalent to std.out.printf(fmt, ...args)

export function printf(fmt: string, ...args: Array<any>): void;

"quickjs:std".sprintf (exported function)​

Equivalent to the libc sprintf().

export function sprintf(fmt: string, ...args: Array<any>): void;

"quickjs:std".in (exported FILE)​

Wrapper to the libc file stdin.

var in_: FILE;

"quickjs:std".in (exported binding)​

export { in_ as in };

"quickjs:std".out (exported FILE)​

Wrapper to the libc file stdout.

var out: FILE;

"quickjs:std".err (exported FILE)​

Wrapper to the libc file stderr.

var err: FILE;

"quickjs:std".SEEK_SET (exported number)​

Constant for FILE.seek. Declares that pointer offset should be relative to the beginning of the file. See also libc fseek().

var SEEK_SET: number;

"quickjs:std".SEEK_CUR (exported number)​

Constant for FILE.seek. Declares that the offset should be relative to the current position of the FILE handle. See also libc fseek().

var SEEK_CUR: number;

"quickjs:std".SEEK_END (exported number)​

Constant for FILE.seek. Declares that the offset should be relative to the end of the file. See also libc fseek().

var SEEK_END: number;

"quickjs:std"._IOFBF (exported number)​

Constant for FILE.setvbuf. Declares that the buffer mode should be 'full buffering'.

var _IOFBF: number;

"quickjs:std"._IOLBF (exported number)​

Constant for FILE.setvbuf. Declares that the buffer mode should be 'line buffering'.

var _IOLBF: number;

"quickjs:std"._IONBF (exported number)​

Constant for FILE.setvbuf. Declares that the buffer mode should be 'no buffering'.

var _IONBF: number;

"quickjs:std".BUFSIZ (exported number)​

The default buffer size for a buffered FILE. Useful for passing into FILE.setvbuf.

var BUFSIZ: number;

"quickjs:std".getenv (exported function)​

Return the value of the environment variable name or undefined if it is not defined.

export function getenv(name: string): string | undefined;

"quickjs:std".setenv (exported function)​

Set the value of the environment variable name to the string value.

export function setenv(name: string, value: string): void;

"quickjs:std".unsetenv (exported function)​

Delete the environment variable name.

export function unsetenv(name: string): void;

"quickjs:std".getenviron (exported function)​

Return an object containing the environment variables as key-value pairs.

export function getenviron(): {
  [key: string]: string | undefined;
};

"quickjs:std".getuid (exported function)​

Return the real user ID of the calling process.

This function throws an error on windows, because windows doesn't support the same uid/gid paradigm as Unix-like operating systems.

export function getuid(): number;

"quickjs:std".geteuid (exported function)​

Return the effective user ID of the calling process.

This function throws an error on windows, because windows doesn't support the same uid/gid paradigm as Unix-like operating systems.

export function geteuid(): number;

"quickjs:std".getgid (exported function)​

Return the real group ID of the calling process.

This function throws an error on windows, because windows doesn't support the same uid/gid paradigm as Unix-like operating systems.

export function getgid(): number;

"quickjs:std".getegid (exported function)​

Return the effective group ID of the calling process.

This function throws an error on windows, because windows doesn't support the same uid/gid paradigm as Unix-like operating systems.

export function getegid(): number;

"quickjs:std".PasswdEntry (exported interface)​

The type of the object returned by getpwuid.

interface PasswdEntry {
  name: string;
  passwd: string;
  uid: number;
  gid: number;
  gecos: string;
  dir: string;
  shell: string;
}

PasswdEntry.name (string property)​

name: string;

PasswdEntry.passwd (string property)​

passwd: string;

PasswdEntry.uid (number property)​

uid: number;

PasswdEntry.gid (number property)​

gid: number;

PasswdEntry.gecos (string property)​

gecos: string;

PasswdEntry.dir (string property)​

dir: string;

PasswdEntry.shell (string property)​

shell: string;

"quickjs:std".getpwuid (exported function)​

Get information from the passwd file entry for the specified user id.

See https://linux.die.net/man/3/getpwuid.

This function throws an error on windows, because windows doesn't support the same uid/gid paradigm as Unix-like operating systems.

export function getpwuid(id: number): PasswdEntry;

"quickjs:std".UrlGet (interface)​

interface UrlGet {
  (url: string): string;
  (
    url: string,
    options: {
      binary: false;
    },
  ): string;
  (
    url: string,
    options: {
      full: false;
    },
  ): string;
  (
    url: string,
    options: {
      binary: false;
      full: false;
    },
  ): string;
  (
    url: string,
    options: {
      binary: true;
    },
  ): ArrayBuffer;
  (
    url: string,
    options: {
      binary: true;
      full: false;
    },
  ): ArrayBuffer;
  (
    url: string,
    options: {
      full: true;
    },
  ): {
    status: number;
    response: string;
    responseHeaders: string;
  };
  (
    url: string,
    options: {
      full: true;
      binary: false;
    },
  ): {
    status: number;
    response: string;
    responseHeaders: string;
  };
  (
    url: string,
    options: {
      full: true;
      binary: true;
    },
  ): {
    status: number;
    response: ArrayBuffer;
    responseHeaders: string;
  };
}

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns string when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string): string;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns string when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string, options: {
  binary: false;
}): string;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns string when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string, options: {
  full: false;
}): string;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns string when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string, options: {
  binary: false;
  full: false;
}): string;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns ArrayBuffer when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string, options: {
  binary: true;
}): ArrayBuffer;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded). Returns ArrayBuffer when the http status code is between 200 and 299, and throws otherwise.

Pass an object with { full: true } as the second argument to get response headers and status code.

(url: string, options: {
  binary: true;
  full: false;
}): ArrayBuffer;

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded).

Returns an object with three properties:

  • response: response body content (string)
  • responseHeaders: headers separated by CRLF (string)
  • status: status code (number)
(url: string, options: {
  full: true;
}): {
  status: number;
  response: string;
  responseHeaders: string;
};

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded).

Returns an object with three properties:

  • response: response body content (string)
  • responseHeaders: headers separated by CRLF (string)
  • status: status code (number)
(url: string, options: {
  full: true;
  binary: false;
}): {
  status: number;
  response: string;
  responseHeaders: string;
};

UrlGet(...) (call signature)​

Download url using libcurl (dynamically loaded).

Returns an object with three properties:

  • response: response body content (ArrayBuffer)
  • responseHeaders: headers separated by CRLF (string)
  • status: status code (number)
(url: string, options: {
  full: true;
  binary: true;
}): {
  status: number;
  response: ArrayBuffer;
  responseHeaders: string;
};

"quickjs:std".urlGet (exported UrlGet)​

var urlGet: UrlGet;

"quickjs:std".parseExtJSON (exported function)​

Parse str using a superset of JSON.parse. The following extensions are accepted:

  • Single line and multiline comments
  • unquoted properties (ASCII-only Javascript identifiers)
  • trailing comma in array and object definitions
  • single quoted strings
  • \f and \v are accepted as space characters
  • leading plus in numbers
  • octal (0o prefix) and hexadecimal (0x prefix) numbers
export function parseExtJSON(str: string): any;

"quickjs:std".strftime (exported function)​

A wrapper around the standard C strftime. Formats a time/date into a format as specified by the user.

  • @param maxBytes — The number of bytes to allocate for the string that will be returned
  • @param format — Format string, using %-prefixed sequences as found in this table.
  • @param time — The Date object (or unix timestamp, in ms) to render.
export function strftime(
  maxBytes: number,
  format: string,
  time: Date | number,
): string;