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How does the fork() function behave in if statements?


How does the fork() function behave in if statements?

By : G.NorthSouth
Date : September 23 2020, 11:00 PM
Hope that helps to your question, how was the output achieved?
following discussion assumes fork() always successful
code :
fork();
// now have both parent and child processes

if (!fork())
// total of 4 processes
// now have a parent and a child process for each of the prior parent and child process 
// but only the two child processes are executing inside this `if` body
{

    if (fork())
    // now have 6 processes
    // now have another parent and child process for each of the prior processes 
    // but only the two new parent processes are executing inside this `if` body
    {
        x++;
    }


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Why does else behave differently in for/while statements as opposed to if/try statements?

Why does else behave differently in for/while statements as opposed to if/try statements?


By : user1509725
Date : March 29 2020, 07:55 AM
wish helps you Well, it depends how you see it. You can look at the elses like this (excuse the screaming, its the only way to make emphasis in code):
code :
if condition:
   do_something()
IF THE PREVIOUS CONDITION WAS FALSE:
   do_something_else()
try:
   do_something()
IF THERE WAS AN EXCEPTION:
   pass:
IF THE PREVIOUS CONDITION WAS FALSE:
   do_something_else()
finally:
   cleanup()
IF some_iterator IS NOT EMPTY:
   i = next(some_iterator)
   print(i)
IF THE PREVIOUS CONDITION WAS FALSE:
   print("Iterator is empty!")
try:
   do_something()
except someException:
   pass:
IF NO EXCEPTION:
   do_something_else()
finally:
   cleanup()
for i in some_iterator:
   print(i)
IF NO MORE ITERATING:
   print("Iterator is empty!")
if condition:
   do_something()
elif otherconditaion:
   do_anotherthing()
IF NO CONDITION WAS TRUE:
   do_something_else()
CreateThread seems to behave like fork()

CreateThread seems to behave like fork()


By : user3140889
Date : March 29 2020, 07:55 AM
Hope this helps You are not clearing the stringstream ss in the loop, so the output just accumulates:
System Verilog fork confusion, statements executed between fork and begin

System Verilog fork confusion, statements executed between fork and begin


By : Icebergman_NewProgra
Date : March 29 2020, 07:55 AM
I think the issue was by ths following , This code fragment looks like it is demonstrating process control so here's my guess as to what's going on. There is a group of processes in arr_obj1s and arr_obj2s:
Those in arr_obj1s run forever so they only need to be spawned once and forgotten about. Those in arr_obj2s accomplish some task and return, so the parent process needs to know when this happens. All processes have the same parent
code :
foreach (arr_obj1s[i]) begin
  fork
    automatic int j = i; // Spawns process
    arr_obj1s[j].run();  // Spawns process
    arr_obj2s[j].run();  // Spawns process
  join_none
end
foreach (arr_obj1s[i]) begin
  fork
    automatic int j = i;
    arr_obj1s[j].run();
    job[j] = process::self(); // Will return parent process
    arr_obj2s[j].run();
  join_none
end
foreach (arr_obj1s[i]) begin
  fork
    automatic int j = i;
    arr_obj1s[j].run(); // Spawns a new process for those that don't complete
    begin               // Spawns a new process for those that complete
      job[j] = process::self(); // Saves handle to this begin..end process
      arr_obj2s[j].run();       // Process continues though here
    end
  join_none
end
How can I see print() statements in behave (BDD)

How can I see print() statements in behave (BDD)


By : Iam Mast Mind Akoo
Date : March 29 2020, 07:55 AM
should help you out I figured it out after spending more time reading the documentation. It is actually quite simple. By default, behave does not display any output (i.e. by using print()) unless there is a failure in the test. To force displaying all output regardless of the outcome of the test (pass/fail), all you need is to change some of the default settings. The easiest way to achieve that is to create a file named behave.ini in the root of your project's directory and put the following:
Filename: behave.ini
code :
[behave]
stderr_capture=False
stdout_capture=False
Why does my fork() doesn't fork a child and output the print statements?

Why does my fork() doesn't fork a child and output the print statements?


By : user2586291
Date : March 29 2020, 07:55 AM
hop of those help? The child process continues to execute the code of the caller. The caller is most likely not expecting to execute the parent and all the children. You should exit the child before that happens:
code :
for (i = 0; i < proc; ++i){
    printf("In for %d",i);
    fflush(stdout); // <--- here
    // TODO
    int fork_result = fork();
    if (fork_result == 0){ // Create child process
        child_pids[i] = getpid();
        printf("Test 5");
        printf("In if %d",i);
        exit(0);  // <---- must have this
        break;
    }
    else if(fork_result < 0){
      printf("Fork failed");
    }
    else if (fork_result > 0){
      printf("Parent");
    }
}
// without the exit above the child will execute this code:
Some code
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