File Management Subsystem ChangeLog

cl.filemanagement.1 File I/O API Changes

The return value of file I/O APIs of file_api does not contain the error code. The original APIs are deprecated, and new APIs are added.

Change Impacts

For applications developed based on earlier versions, pay attention to the iterative update of discarded APIs. The specifications of the new APIs are slightly adjusted. Pay attention to the usage of the new APIs.

Key API/Component Changes

For the adaptation to the unified API exception handling mode, related file I/O APIs are deprecated, and corresponding new APIs are added. Original APIs are stored in @ohos.fileio, and the new ones are stored in @ohos.file.fs. The newly added APIs support unified error code handling specifications and function the same as the original APIs. The parameters are slightly adjusted.

Module	Method/Attribute/Enumeration/Constant	Change Type
@ohos.fileio	function open(path: string, flags?: number, mode?: number, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function openSync(path: string, flags?: number, mode?: number): number;	Deprecated
@ohos.file.fs	function open(path: string, mode?: number, callback?: AsyncCallback): void \|Promise;	Added
@ohos.file.fs	function openSync(path: string, mode?: number): File;	Added
@ohos.fileio	function read(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; position?: number; }, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function readSync(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; position?: number; }): number;	Deprecated
@ohos.file.fs	function read(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; }, callback?: AsyncCallback): void \|Promise;	Added
@ohos.file.fs	function readSync(fd: number, buffer: ArrayBuffer, options?: { offset?: number; length?: number; }): number;	Added
@ohos.fileio	function stat(path: string, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function statSync(path: string): Stat;	Deprecated
@ohos.fileio	function fstat(fd: number, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function fstatSync(fd: number): Stat;	Deprecated
@ohos.file.fs	function stat(file: string \|number, callback?: AsyncCallback): void \|Promise;	Added
@ohos.file.fs	function statSync(file: string \|number): Stat;	Added
@ohos.fileio	function truncate(path: string, len?: number, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function truncateSync(path: string, len?: number): void;	Deprecated
@ohos.fileio	function ftruncate(fd: number, len?: number, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function ftruncateSync(fd: number, len?: number): void;	Deprecated
@ohos.file.fs	function truncate(file: string \|number, len?: number, callback?: AsyncCallback): void \|Promise;	Added
@ohos.file.fs	function truncateSync(file: string \|number, len?: number): void;	Added
@ohos.fileio	function write(fd: number, buffer: ArrayBuffer \|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }, callback?: AsyncCallback): void \|Promise;	Deprecated
@ohos.fileio	function writeSync(fd: number, buffer: ArrayBuffer \|string, options?: { offset?: number; length?: number; position?: number; encoding?: string; }): number;	Deprecated
@ohos.file.fs	function write(fd: number, buffer: ArrayBuffer \|string, options?: { offset?: number; length?: number; encoding?: string; }, callback?: AsyncCallback): void \|Promise;	Added
@ohos.file.fs	function writeSync(fd: number, buffer: ArrayBuffer \|string, options?: { offset?: number; length?: number; encoding?: string; }): number;	Added

Adaptation Guide

The original APIs use @ohos.fileio, which is imported as follows:

import fileio from '@ohos.fileio';

The new APIs use @ohos.file.fs, which is imported as follows:

import fs from '@ohos.file.fs';

In addition, exception handling needs to be adapted. Sample code for synchronous API exception handling is as follows:

import fs from '@ohos.file.fs'

try {
    let file = fs.openSync(path, fs.OpenMode.READ_ONLY);
} catch (err) {
    console.error("openSync errCode:" + err.code + ", errMessage:" + err.message);
}

Sample code for handling exceptions of the promise method of an asynchronous API:

import fs from '@ohos.file.fs'

try {
    let file = await fs.open(path, fs.OpenMode.READ_ONLY);
} catch (err) {
    console.error("open promise errCode:" + err.code + ", errMessage:" + err.message);
}

Sample code for handling exceptions of the callback method of an asynchronous API:

import fs from '@ohos.file.fs'

try {
    fs.open(path, fs.OpenMode.READ_ONLY, function(e, file){ // Asynchronous thread (such as system call) errors are obtained from the callback.
        if (e) {
            console.error("open in async errCode:" + e.code + ", errMessage:" + e.message);
        }
    });
} catch (err) {// Errors (such as invalid parameters) of the main thread are obtained through try catch.
    console.error("open callback errCode:" + err.code + ", errMessage:" + err.message);
}