OS module in Python provides functions for interacting with the operating system. OS comes under Python’s standard utility modules. This module provides a portable way of using operating system dependent functionality.
os.waitid() method in Python is used by a process to wait for completion of one or more child processes.
Syntax: os.waitid(idtype, id, options)
Parameters:
id: An integer value representing the process id of child to wait on.
idtype: The idtype and id parameter specify which child the method waits for.Return type: This method returns an object which represents the data contained in siginfo_t structure.
Code #1: Use of os.waitid() method
# Python program to explain os.waitid() method # importing os module import os # Create a child process # using os.fork() method pid = os.fork() # a Non-zero process id (pid) # indicates the parent process if pid : # Wait for the completion of # child process using # os.waitid() method # Specify idtype idtype = os.P_PID # Specify id id = pid # Specify option option = os.WEXITED status = os.waitid(idtype, id, option) print("\nIn parent process-") # Print status print("Status of child process:") print(status) else : print("In Child process-") print("Process ID:", os.getpid()) print("Hello ! Geeks") print("Exiting..") |
Output:
In Child process- Process ID: 10309 Hello! Geeks Exiting.. In parent process- Status of child process: posix.waitid_result(si_pid=10309, si_uid=1000, si_signo=17, si_status=0, si_code=1)
Code #2: Use of os.waitid() method
# Python program to explain os.waitid() method # importing os module import os # Create a child process # using os.fork() method pid = os.fork() # a Non-zero process id (pid) # indicates the parent process if pid : # Create one more child process pid2 = os.fork() if pid2 : # Wait for the completion of # any child processes using # os.waitid() method # Specify idtype idtype = os.P_ALL # Specify id # As idtype is os.P_ALL # method will wait for # any children and specified id # is ignored. id = pid # Specify option option = os.WSTOPPED | os.WEXITED status = os.waitid(idtype, id, option) print("\nIn parent process-") # Print status print("Status of completed child process:") print(status) else : print("\nIn Second Child process-") print("Process ID:", os.getpid()) print("Hey ! There ") print("Exiting") else : print("In First Child process-") print("Process ID:", os.getpid()) print("Hello ! Geeks") print("Exiting") |
Output:
In First Child process- Process ID: 11524 Hello! Geeks Exiting In Second Child process- Process ID: 11525 Hey! There Exiting In parent process- Status of completed child process: posix.waitid_result(si_pid=11524, si_uid=1000, si_signo=17, si_status=0, si_code=1)
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