@ohos.process (Obtaining Process Information)

The process module provides process management APIs, for example, APIs for obtaining process information.

NOTE

The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version.

Modules to Import

import process from '@ohos.process';

Attributes

System capability: SystemCapability.Utils.Lang

Name Type Readable Writable Description
uid number Yes No User identifier (UID) of the process.
pid number Yes No Process ID (PID) of the process.
tid8+ number Yes No Thread ID (TID) of the thread.

EventListener

System capability: SystemCapability.Utils.Lang

Name Description
EventListener = (evt:  Object) => void Event to store.

process.isIsolatedProcess8+

isIsolatedProcess(): boolean

Checks whether this process is isolated.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
boolean Returns true if the process is isolated; returns false otherwise.

Example

let result = process.isIsolatedProcess();

process.is64Bit8+

is64Bit(): boolean

Checks whether this process is running in a 64-bit environment.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
boolean Returns true if the process is running in a 64-bit environment; returns false otherwise.

Example

let result = process.is64Bit();

process.getStartRealtime8+

getStartRealtime(): number

Obtains the duration, in milliseconds, from the time the system starts to the time the process starts.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number Duration obtained, in millisecond.

Example

let realtime = process.getStartRealtime();

process.getPastCpuTime8+

getPastCpuTime(): number

Obtains the CPU time (in milliseconds) from the time the process starts to the current time.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number CPU time obtained, in millisecond.

Example

let result = process.getPastCpuTime() ;

process.abort

abort(): void

Aborts a process and generates a core file. This method will cause a process to exit immediately. Exercise caution when using this method.

System capability: SystemCapability.Utils.Lang

Example

process.abort();

process.uptime

uptime(): number

Obtains the running time of this process.

System capability: SystemCapability.Utils.Lang

Return value

Type Description
number Running time of the process, in seconds.

Example

let time = process.uptime();

process.kill(deprecated)

kill(signal: number, pid: number): boolean

Sends a signal to the specified process to terminate it.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use kill9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
signal number Yes Signal to send.
pid number Yes PID of the process, to which the signal will be sent.

Return value

Type Description
boolean Returns true if the signal is sent successfully; returns false otherwise.

Example

let pres = process.pid
let result = process.kill(28, pres)

process.exit(deprecated)

exit(code: number): void

Terminates this process.

Exercise caution when using this API. After this API is called, the application exits. If the input parameter is not 0, data loss or exceptions may occur.

NOTE

This API is supported since API version 7 and deprecated since API version 9. You are advised to use exit9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
code number Yes Exit code of the process.

Example

process.exit(0);

process.getUidForName(deprecated)

getUidForName(v: string): number

Obtains the process UID based on the process name.

NOTE

This API is supported since API version 8 and deprecated since API version 9. You are advised to use getUidForName9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v string Yes Name of a process.

Return value

Type Description
number Process UID.

Example

let pres = process.getUidForName("tool")

process.getThreadPriority(deprecated)

getThreadPriority(v: number): number

Obtains the thread priority based on the specified TID.

NOTE

This API is supported since API version 8 and deprecated since API version 9. You are advised to use getThreadPriority9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v number Yes TID.

Return value

Type Description
number Priority of the thread. The priority depends on the operating system.

Example

let tid = process.tid;
let pres = process.getThreadPriority(tid);

process.isAppUid(deprecated)

isAppUid(v: number): boolean

Checks whether a UID belongs to this application.

NOTE

This API is supported since API version 8 and deprecated since API version 9. You are advised to use isAppUid9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v number Yes UID.

Return value

Type Description
boolean Returns true if the UID belongs to the application; returns false otherwise.

Example

let result = process.isAppUid(688);

process.getSystemConfig(deprecated)

getSystemConfig(name: number): number

Obtains the system configuration.

NOTE

This API is supported since API version 8 and deprecated since API version 9. You are advised to use getSystemConfig9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name number Yes System configuration parameter name.

Return value

Type Description
number System configuration obtained.

Example

let _SC_ARG_MAX = 0
let pres = process.getSystemConfig(_SC_ARG_MAX)

process.getEnvironmentVar(deprecated)

getEnvironmentVar(name: string): string

Obtains the value of an environment variable.

NOTE

This API is supported since API version 8 and deprecated since API version 9. You are advised to use getEnvironmentVar9+ instead.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name string Yes Environment variable name.

Return value

Type Description
string Value of the environment variable.

Example

let pres = process.getEnvironmentVar("PATH")

ProcessManager9+

Provides APIs for throwing exceptions during the addition of a process.

A ProcessManager object is obtained through its own constructor.

isAppUid9+

isAppUid(v: number): boolean

Checks whether a UID belongs to this application.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v number Yes UID.

Return value

Type Description
boolean Returns true if the UID belongs to the application; returns false otherwise.

Example

let pro = new process.ProcessManager();
let result = pro.isAppUid(688);

getUidForName9+

getUidForName(v: string): number

Obtains the process UID based on the process name.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v string Yes Name of a process.

Return value

Type Description
number Process UID.

Example

let pro = new process.ProcessManager();
let pres = pro .getUidForName("tool");

getThreadPriority9+

getThreadPriority(v: number): number

Obtains the thread priority based on the specified TID.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
v number Yes TID.

Return value

Type Description
number Priority of the thread. The priority depends on the operating system.

Example

let pro = new process.ProcessManager();
let tid = process.tid;
let pres = pro.getThreadPriority(tid);

getSystemConfig9+

getSystemConfig(name: number): number

Obtains the system configuration.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name number Yes System configuration parameter name.

Return value

Type Description
number System configuration obtained.

Example

let pro = new process.ProcessManager();
let _SC_ARG_MAX = 0;
let pres = pro.getSystemConfig(_SC_ARG_MAX);

getEnvironmentVar9+

getEnvironmentVar(name: string): string

Obtains the value of an environment variable.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
name string Yes Environment variable name.

Return value

Type Description
string Value of the environment variable.

Example

let pro = new process.ProcessManager();
let pres = pro.getEnvironmentVar("PATH");

exit9+

exit(code: number): void

Terminates this process.

Exercise caution when using this API. After this API is called, the application exits. If the input parameter is not 0, data loss or exceptions may occur.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
code number Yes Exit code of the process.

Example

let pro = new process.ProcessManager();
pro.exit(0);

kill9+

kill(signal: number, pid: number): boolean

Sends a signal to the specified process to terminate it.

System capability: SystemCapability.Utils.Lang

Parameters

Name Type Mandatory Description
signal number Yes Signal to send.
pid number Yes PID of the process, to which the signal will be sent.

Return value

Type Description
boolean Returns true if the signal is sent successfully; returns false otherwise.

Example

let pro = new process.ProcessManager();
let pres = process.pid;
let result = pro.kill(28, pres);