process
Extensions to process object.
Electron's process
object is extended from the Node.js process
object. It adds the following events, properties, and methods:
Sandbox
In sandboxed renderers the process
object contains only a subset of the APIs:
crash()
hang()
getCreationTime()
getHeapStatistics()
getBlinkMemoryInfo()
getProcessMemoryInfo()
getSystemMemoryInfo()
getSystemVersion()
getCPUUsage()
uptime()
argv
execPath
env
pid
arch
platform
sandboxed
contextIsolated
type
version
versions
mas
windowsStore
contextId
Events
Event: 'loaded'
Emitted when Electron has loaded its internal initialization script and is beginning to load the web page or the main script.
Properties
process.defaultApp
Readonly
A boolean
. When the app is started by being passed as parameter to the default Electron executable, this property is true
in the main process, otherwise it is undefined
. For example when running the app with electron .
, it is true
, even if the app is packaged (isPackaged
) is true
. This can be useful to determine how many arguments will need to be sliced off from process.argv
.
process.isMainFrame
Readonly
A boolean
, true
when the current renderer context is the "main" renderer frame. If you want the ID of the current frame you should use webFrame.routingId
.
process.mas
Readonly
A boolean
. For Mac App Store build, this property is true
, for other builds it is undefined
.
process.noAsar
A boolean
that controls ASAR support inside your application. Setting this to true
will disable the support for asar
archives in Node's built-in modules.
process.noDeprecation
A boolean
that controls whether or not deprecation warnings are printed to stderr
. Setting this to true
will silence deprecation warnings. This property is used instead of the --no-deprecation
command line flag.
process.resourcesPath
Readonly
A string
representing the path to the resources directory.
process.sandboxed
Readonly
A boolean
. When the renderer process is sandboxed, this property is true
, otherwise it is undefined
.
process.contextIsolated
Readonly
A boolean
that indicates whether the current renderer context has contextIsolation
enabled. It is undefined
in the main process.
process.throwDeprecation
A boolean
that controls whether or not deprecation warnings will be thrown as exceptions. Setting this to true
will throw errors for deprecations. This property is used instead of the --throw-deprecation
command line flag.
process.traceDeprecation
A boolean
that controls whether or not deprecations printed to stderr
include their stack trace. Setting this to true
will print stack traces for deprecations. This property is instead of the --trace-deprecation
command line flag.
process.traceProcessWarnings
A boolean
that controls whether or not process warnings printed to stderr
include their stack trace. Setting this to true
will print stack traces for process warnings (including deprecations). This property is instead of the --trace-warnings
command line flag.
process.type
Readonly
A string
representing the current process's type, can be:
browser
- The main processrenderer
- A renderer processworker
- In a web workerutility
- In a node process launched as a service
process.versions.chrome
Readonly
A string
representing Chrome's version string.
process.versions.electron
Readonly
A string
representing Electron's version string.
process.windowsStore
Readonly
A boolean
. If the app is running as a Windows Store app (appx), this property is true
, for otherwise it is undefined
.
process.contextId
Readonly
A string
(optional) representing a globally unique ID of the current JavaScript context. Each frame has its own JavaScript context. When contextIsolation is enabled, the isolated world also has a separate JavaScript context. This property is only available in the renderer process.
process.parentPort
A Electron.ParentPort
property if this is a UtilityProcess
(or null
otherwise) allowing communication with the parent process.
Methods
The process
object has the following methods:
process.crash()
Causes the main thread of the current process crash.
process.getCreationTime()
Returns number | null
- The number of milliseconds since epoch, or null
if the information is unavailable
Indicates the creation time of the application. The time is represented as number of milliseconds since epoch. It returns null if it is unable to get the process creation time.
process.getCPUUsage()
Returns CPUUsage
process.getHeapStatistics()
Returns Object
:
totalHeapSize
IntegertotalHeapSizeExecutable
IntegertotalPhysicalSize
IntegertotalAvailableSize
IntegerusedHeapSize
IntegerheapSizeLimit
IntegermallocedMemory
IntegerpeakMallocedMemory
IntegerdoesZapGarbage
boolean
Returns an object with V8 heap statistics. Note that all statistics are reported in Kilobytes.
process.getBlinkMemoryInfo()
Returns Object
:
allocated
Integer - Size of all allocated objects in Kilobytes.total
Integer - Total allocated space in Kilobytes.
Returns an object with Blink memory information. It can be useful for debugging rendering / DOM related memory issues. Note that all values are reported in Kilobytes.
process.getProcessMemoryInfo()
Returns Promise<ProcessMemoryInfo>
- Resolves with a ProcessMemoryInfo
Returns an object giving memory usage statistics about the current process. Note that all statistics are reported in Kilobytes. This api should be called after app ready.
Chromium does not provide residentSet
value for macOS. This is because macOS performs in-memory compression of pages that haven't been recently used. As a result the resident set size value is not what one would expect. private
memory is more representative of the actual pre-compression memory usage of the process on macOS.
process.getSystemMemoryInfo()
Returns Object
:
total
Integer - The total amount of physical memory in Kilobytes available to the system.free
Integer - The total amount of memory not being used by applications or disk cache.swapTotal
Integer Windows Linux - The total amount of swap memory in Kilobytes available to the system.swapFree
Integer Windows Linux - The free amount of swap memory in Kilobytes available to the system.
Returns an object giving memory usage statistics about the entire system. Note that all statistics are reported in Kilobytes.
process.getSystemVersion()
Returns string
- The version of the host operating system.
Example:
const version = process.getSystemVersion()
console.log(version)
// On macOS -> '10.13.6'
// On Windows -> '10.0.17763'
// On Linux -> '4.15.0-45-generic'
Note: It returns the actual operating system version instead of kernel version on macOS unlike os.release()
.
process.takeHeapSnapshot(filePath)
filePath
string - Path to the output file.
Returns boolean
- Indicates whether the snapshot has been created successfully.
Takes a V8 heap snapshot and saves it to filePath
.
process.hang()
Causes the main thread of the current process hang.
process.setFdLimit(maxDescriptors)
macOS Linux
maxDescriptors
Integer
Sets the file descriptor soft limit to maxDescriptors
or the OS hard limit, whichever is lower for the current process.