> The initial APIs of this module are supported since API version 6. Newly added APIs will be marked with a superscript to indicate their earliest API version.
This module provides common file storage functions. It provides the following JavaScript I/O APIs, including:
- Basic APIs for file management
- Basic APIs for directory management
- Statistical APIs for obtaining file information
- Stream APIs for reading and writing files
Provides file storage and management capabilities, including basic file management, file directory management, file information statistics, and stream read and write.
## Modules to Import
...
...
@@ -19,22 +14,11 @@ import fileio from '@ohos.fileio';
## Guidelines
Before using this module to perform operations on a file or directory, obtain the absolute path of the file or directory. For details, see [getOrCreateLocalDir of the Context module](js-apis-Context.md).
Absolute file or directory path = Application directory + File name or directory name
For example, if the application directory obtained by using **getOrCreateLocalDir** is **dir** and the file name is **xxx.txt**, the absolute path of the file is as follows:
```js
letpath=dir+"/xxx.txt";
```
The file descriptor is as follows:
```js
letfd=fileio.openSync(path);
Before using the APIs provided by this module to perform operations on files or directories, obtain the path of the application sandbox as follows:
| path | string | Yes | Absolute path of the target file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
| path | string | Yes | Application sandbox path of the file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
| path | string | Yes | Absolute path of the target file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the file is asynchronously checked. |
| path | string | Yes | Application sandbox path of the file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the file is asynchronously checked. |
**Example**
```js
...
...
@@ -258,10 +242,10 @@ Synchronously checks whether the current process can access the specified file.
| path | string | Yes | Absolute path of the target file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
| path | string | Yes | Application sandbox path of the file. |
| mode | number | No | Options for accessing the file. You can specify multiple options, separated with a bitwise OR operator (|). The default value is **0**.<br>The options are as follows:<br>- **0**: check whether the file exists.<br>- **1**: check whether the current process has the execute permission on the file.<br>- **2**: check whether the current process has the write permission on the file.<br>- **4**: check whether the current process has the read permission on the file.|
**Example**
```js
...
...
@@ -277,7 +261,7 @@ Synchronously checks whether the current process can access the specified file.
close(fd: number):Promise<void>
Asynchronously closes a file. This API uses a promise to return the result.
Closes a file. This API uses a promise to return the result asynchronously.
| path | string | Yes | Absolute path of the directory to create. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Application sandbox path of the directory. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Absolute path of the directory to create. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the directory is created asynchronously. |
| path | string | Yes | Application sandbox path of the directory. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the directory is created asynchronously. |
**Example**
```js
fileio.mkdir(path,function(err){
console.info("mkdir successfully");
console.info("mkdir succeed");
});
```
...
...
@@ -524,10 +508,10 @@ Synchronously creates a directory.
| path | string | Yes | Absolute path of the directory to create. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Application sandbox path of the directory. |
| mode | number | No | Permission on the directory to create. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o775**.<br>- **0o775**: The owner has the read, write, and execute permissions, and other users have the read and execute permissions.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
**Example**
```js
...
...
@@ -539,26 +523,26 @@ Synchronously creates a directory.
| path | string | Yes | Absolute path of the target file. |
| flags | number | No | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | No | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Application sandbox path of the file. |
| flags | number | No | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | No | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
**Return value**
| Type | Description |
| --------------------- | ----------- |
| Promise<number> | File descriptor of the file opened.|
| Promise<number> | Promise used to return the file descriptor of the file opened.|
| path | string | Yes | Absolute path of the target file. |
| flags | number | Yes | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br/>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback <void> | Yes | Callback invoked when the file is open asynchronously. |
| path | string | Yes | Application sandbox path of the file. |
| flags | number | Yes | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback <void> | Yes | Callback invoked when the file is open asynchronously. |
| path | string | Yes | Absolute path of the target file. |
| flags | number | No | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br/>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | No | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.<br>The file permissions on newly created files are affected by umask, which is set as the process starts. Currently, the modification of umask is not open.|
| path | string | Yes | Application sandbox path of the file. |
| flags | number | No | Option for opening the file. You must specify one of the following options. By default, the file is open in read-only mode.<br>- **0o0**: Open the file in read-only mode.<br>- **0o1**: Open the file in write-only mode.<br>- **0o2**: Open the file in read/write mode.<br>In addition, you can specify the following options, separated using a bitwise OR operator (|). By default, no additional option is specified.<br>- **0o100**: If the file does not exist, create it. If you use this option, you must also specify **mode**.<br>- **0o200**: If **0o100** is added and the file already exists, throw an exception.<br>- **0o1000**: If the file exists and is open in write-only or read/write mode, truncate the file length to 0.<br>- **0o2000**: Open the file in append mode. New data will be appended to the file (added to the end of the file).<br>- **0o4000**: If **path** points to a named pipe (also known as a FIFO), block special file, or character special file, perform non-blocking operations on the open file and in subsequent I/Os.<br>- **0o200000**: If **path** points to a directory, throw an exception.<br><br>- **0o400000**: If **path** points to a symbolic link, throw an exception.<br>- **0o4010000**: Open the file in synchronous I/O mode.|
| mode | number | No | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|). The default value is **0o666**.<br>- **0o666**: The owner, user group, and other users have the read and write permissions on the file.<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.<br>The file permissions on newly created files are affected by umask, which is set as the process starts. Currently, the modification of umask is not open.|
| path | string | Yes | Absolute path of the target file. |
| algorithm | string | Yes | Algorithm used to calculate the hash value. The value can be **md5**, **sha1**, or **sha256**. **sha256** is recommended for security purposes.|
| path | string | Yes | Application sandbox path of the file. |
| algorithm | string | Yes | Algorithm used to calculate the hash value. The value can be **md5**, **sha1**, or **sha256**. **sha256** is recommended for security purposes.|
| Promise<string> | Promise used to return the hash value of the file. The hash value is a hexadecimal string consisting of digits and uppercase letters.|
| Promise<string> | Promise used to return the hash value obtained. The hash value is a hexadecimal string consisting of digits and uppercase letters.|
| path | string | Yes | Absolute path of the target file. |
| algorithm | string | Yes | Algorithm used to calculate the hash value. The value can be **md5**, **sha1**, or **sha256**. **sha256** is recommended for security purposes.|
| callback | AsyncCallback<string> | Yes | Callback used to return the hash value. The hash value is a hexadecimal string consisting of digits and uppercase letters.|
| path | string | Yes | Application sandbox path of the file. |
| algorithm | string | Yes | Algorithm used to calculate the hash value. The value can be **md5**, **sha1**, or **sha256**. **sha256** is recommended for security purposes.|
| callback | AsyncCallback<string> | Yes | Callback used to return the hash value obtained. The hash value is a hexadecimal string consisting of digits and uppercase letters.|
| path | string | Yes | Absolute path of the target file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Application sandbox path of the file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Absolute path of the target file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the file permissions are changed asynchronously. |
| path | string | Yes | Application sandbox path of the file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| callback | AsyncCallback<void> | Yes | Callback invoked when the file permissions are changed asynchronously. |
**Example**
```js
...
...
@@ -1067,15 +1051,15 @@ Asynchronously changes the file permissions based on its path. This API uses a c
chmodSync(path: string, mode: number): void
Synchronously changes the file permissions based on its path.
| path | string | Yes | Absolute path of the target file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Application sandbox path of the file. |
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
**Example**
```js
...
...
@@ -1087,7 +1071,7 @@ Synchronously changes the file permissions based on its path.
fstat(fd: number): Promise<Stat>
Asynchronously obtains file status information based on the file descriptor. This API uses a promise to return the result.
Obtains file information based on the file descriptor. This API uses a promise to return the result asynchronously.
| filePath | string | Yes | Absolute path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding** (string): format of the data (string) to be encoded. The default value is **utf-8**, which is the only value supported.|
| filePath | string | Yes | Application sandbox path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding** (string): format of the data (string) to be encoded. The default value is **utf-8**, which is the only value supported.|
**Return value**
| Type | Description |
| --------------------- | ---------- |
| Promise<string> | Promise used to return the content of the file read.|
| Promise<string> | Promise used to return the content read.|
| filePath | string | Yes | Absolute path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding** (string): format of the data (string) to be encoded. The default value is **utf-8**, which is the only value supported.|
| callback | AsyncCallback<string> | Yes | Callback invoked when the file is read asynchronously. |
| filePath | string | Yes | Application sandbox path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding**: format of the string to be encoded. The default value is **utf-8**, which is the only value supported.|
| callback | AsyncCallback<string> | Yes | Callback used to return the content read. |
**Example**
```js
...
...
@@ -1377,10 +1361,10 @@ Synchronously reads the text of a file.
| filePath | string | Yes | Absolute path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding** (string): format of the data (string) to be encoded. The default value is **utf-8**, which is the only value supported.|
| filePath | string | Yes | Application sandbox path of the file to read. |
| options | Object | No | The options are as follows:<br>- **position** (number): position of the data to read in the file. By default, data is read from the current position.<br>- **length** (number): length of the data to read. The default value is the buffer length minus the offset.<br>- **encoding** (string): format of the data (string) to be encoded. The default value is **utf-8**, which is the only value supported.|
**Return value**
| Type | Description |
...
...
@@ -1397,24 +1381,24 @@ Synchronously reads the text of a file.
lstat(path: string): Promise<Stat>
Asynchronously obtains link status information. This API uses a promise to return the result.
Obtains link information. This API uses a promise to return the result asynchronously.
| fd | number | Yes | File descriptor of the file to synchronize.|
| fd | number | Yes | File descriptor of the file to flush.|
**Example**
```js
...
...
@@ -1676,7 +1660,7 @@ Synchronizes a file in synchronous mode.
fdatasync(fd: number): Promise<void>
Asynchronously synchronizes data in a file. This API uses a promise to return the result.
Flushes data of a file to disk. This API uses a promise to return the result asynchronously. **fdatasync()** is similar to **fsync()**, but does not flush modified metadata unless that metadata is needed.
@@ -1980,14 +1964,14 @@ Asynchronously changes the file permissions based on the file descriptor. This A
| mode | number | Yes | Permissions on the file. You can specify multiple permissions, separated using a bitwise OR operator (|).<br>- **0o700**: The owner has the read, write, and execute permissions.<br>- **0o400**: The owner has the read permission.<br>- **0o200**: The owner has the write permission.<br>- **0o100**: The owner has the execute permission.<br>- **0o070**: The user group has the read, write, and execute permissions.<br>- **0o040**: The user group has the read permission.<br>- **0o020**: The user group has the write permission.<br>- **0o010**: The user group has the execute permission.<br>- **0o007**: Other users have the read, write, and execute permissions.<br>- **0o004**: Other users have the read permission.<br>- **0o002**: Other users have the write permission.<br>- **0o001**: Other users have the execute permission.|
| path | string | Yes | Absolute path of the target file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
| path | string | Yes | Application sandbox path of the file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
**Return value**
| Type | Description |
...
...
@@ -2059,7 +2043,7 @@ Asynchronously opens a stream based on the file path. This API uses a promise to
| path | string | Yes | Absolute path of the target file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
| callback | AsyncCallback<[Stream](#stream7)> | Yes | Callback invoked when the stream is open asynchronously. |
| path | string | Yes | Application sandbox path of the file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
| callback | AsyncCallback<[Stream](#stream7)> | Yes | Callback invoked when the stream is open asynchronously. |
**Example**
```js
...
...
@@ -2098,13 +2082,13 @@ Synchronously opens a stream based on the file path.
| path | string | Yes | Absolute path of the target file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
| path | string | Yes | Application sandbox path of the file. |
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
**Return value**
| Name | Description |
| Type | Description |
| ------------------ | --------- |
| [Stream](#stream7) | Stream opened.|
...
...
@@ -2118,7 +2102,7 @@ Synchronously opens a stream based on the file path.
@@ -2129,14 +2113,14 @@ Asynchronously opens a stream based on the file descriptor. This API uses a prom
| mode | string | Yes | - **r**: Open a file for reading. The file must exist.<br>- **r+**: Open a file for both reading and writing. The file must exist.<br>- **w**: Open a file for writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **w+**: Open a file for both reading and writing. If the file exists, clear its content. If the file does not exist, create a file.<br>- **a**: Open a file in append mode for writing at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).<br>- **a+**: Open a file in append mode for reading or updating at the end of the file. If the file does not exist, create a file. If the file exists, write data to the end of the file (the original content of the file is reserved).|
**Return value**
| Name | Description |
| Type | Description |
| --------------------------------- | --------- |
| Promise<[Stream](#stream7)> | Promise used to return the result.|
Asynchronously changes the file owner based on the file path, changes the owner of the symbolic link (not the referenced file), and returns the result in a promise.
Changes the file owner (owner of the symbolic link, not the file referred to by the symbolic link) based on the file path. This API uses a promise to return the result asynchronously.
Asynchronously changes the file owner based on the file path, changes the owner of the symbolic link (not the referenced file), and returns the result in a callback.
Changes the file owner (owner of the symbolic link, not the file referred to by the symbolic link) based on the file path. This API uses an asynchronous callback to return the result.
| filename | string | Yes | Absolute path of the target file. |
| events | Number | Yes | - **1**: The file or directory is renamed.<br>- **2**: The file or directory is modified.<br>- **3**: The file or directory is modified and renamed.|
| callback | AsyncCallback<number > | Yes | Called each time a change is detected. |
| filename | string | Yes | Application sandbox path of the file. |
| events | Number | Yes | - **1**: The file or directory is renamed.<br>- **2**: The file or directory is modified.<br>- **3**: The file or directory is modified and renamed.|
| callback | AsyncCallback<number > | Yes | Called each time a change is detected. |
**Return value**
| Name | Description |
| Type | Description |
| -------------------- | ---------- |
| [Watcher](#watcher7) | Instance for listening for a file change event.|
| [Watcher](#watcher7) | Promise used to return the **Watcher** instance.|
**Example**
```js
...
...
@@ -2554,7 +2538,7 @@ Listens for the changes of a file. You can call the **Watcher.stop()** method sy
stop(): Promise<void>
Asynchronously stops **watcher**. This API uses a promise to return the result.
Stops the **watcher** instance. This API uses a promise to return the result asynchronously.
@@ -2585,17 +2569,16 @@ Asynchronously stops **watcher**. This API uses a callback to return the result.
```
## Stream<sup>7+</sup>
File stream. Before calling a method of the **Stream** class, use the **createStream()** method synchronously or asynchronously to create a **Stream** instance.
Provides file stream management. Before calling a method of the **Stream** class, use the **createStream()** method synchronously or asynchronously to create a **Stream** instance.
### close<sup>7+</sup>
close(): Promise<void>
Asynchronously closes the stream. This API uses a promise to return the result.
Closes the stream. This API uses a promise to return the result asynchronously.
@@ -3015,7 +2998,7 @@ Provides information about files and directories. Before calling a method of the
isBlockDevice(): boolean
Checks whether the current directory entry is a block special file. A block special file supports access by block only, and it is cached when accessed.
Checks whether this directory entry is a block special file. A block special file supports access by block only, and it is cached when accessed.
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
Manages file data security levels, including obtaining and setting file data security levels.
## Modules to Import
```js
importsecurityLabelfrom'@ohos.securityLabel';
```
## Usage
Before using the APIs provided by this module to perform operations on a file or directory, obtain the path of the application sandbox. For details, see [getOrCreateLocalDir of the Context module](js-apis-Context.md).
Application sandbox path of a file or directory = Application directory + File name or directory name
For example, if the application directory obtained by using **getOrCreateLocalDir** is **dir** and the file name is **xxx.txt**, the application sandbox path of the file is as follows:
> The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version.
Obtains file system information, including the total number of bytes and the number of idle bytes of the file system.
## Modules to Import
```js
importstatfsfrom'@ohos.statfs';
```
## Guidelines
Before using this module to perform operations on a file or directory, obtain the absolute path of the file or directory. For details, see [getOrCreateLocalDir of the Context module](js-apis-Context.md).
Absolute file or directory path = Application directory + File name or directory name
For example, if the application directory obtained by using **getOrCreateLocalDir** is **dir** and the file name is **xxx.txt**, the absolute path of the file is as follows:
```js
letpath=dir+"xxx.txt";
```
## statfs.getFreeBytes
getFreeBytes(path:string):Promise<number>
Obtains the number of free bytes of the specified file system in asynchronous mode. This method uses a promise to return the result.
Obtains the number of free bytes of the specified file system in asynchronous mode. This API uses a promise to return the result.
