@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);