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WASI
proc_exit

proc_exit()

Terminate the process normally. An exit code of 0 indicates successful termination of the program. The meanings of other values are dependent on the environment.

Description

The proc_exit() function is similar to the exit() function in POSIX systems. It allows the program to gracefully terminate with an exit code. The provided exit code is returned to the operating system.

Syntax

  ;;; the environment.
  ;;; termination of the program. The meanings of other values is dependent on
  ;;; Terminate the process normally. An exit code of 0 indicates successful
  (@interface func (export "proc_exit")
    ;;; The exit code returned by the process.
    (param $rval $exitcode)
    (@witx noreturn)
  )

Parameters

  • ctx: A mutable reference to the function environment.
  • code: The exit code to return to the operating system.

Return Value

This function returns Result<(), WasiError>. If the termination is successful, it returns Ok(()). Otherwise, it returns an appropriate WasiError indicating the cause of the failure.

Logging

This function is instrumented with debug level logging. It includes the following fields for debugging purposes:

  • code: The exit code provided as input.

Notes

  • The behavior of proc_exit() is similar to the POSIX exit() function, which terminates the calling process.
  • The exit() function in POSIX does not have a return value, as the termination of the process is immediate.
  • It is important to note that proc_exit() is specific to the WASIX system call toolchain for WebAssembly and may have slight differences from the POSIX exit() function.
  • In POSIX systems, the exit() function is usually called at the end of the program or when an error occurs that requires immediate termination.
  • The exit code returned by proc_exit() can be used by the parent process or by the operating system to determine the status of the terminated process.
  • The meanings of exit codes other than 0 depend on the specific environment or application. In POSIX systems, non-zero exit codes are often used to indicate different types of errors or exceptional conditions.
  • When writing portable code, it is important to consider the exit code meanings in the target environment and ensure proper handling of different exit codes.
poll_oneoffproc_raise