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POparent doesn't create child?
primarykey
Id
10667350
data
AcceptedAnswerId
10667442
AnswerCount
1
ClosedDate
CommentCount
3
CommunityOwnedDate
CreationDate
2012-05-19T17:20:11.303
FavoriteCount
0
LastActivityDate
2012-05-19T17:46:28.117
LastEditDate
2012-05-19T17:26:00.993
LastEditorUserId
1335101
OwnerUserId
1335101
ParentId
0
PostTypeId
1
Score
1
ViewCount
87
LastEditorDisplayName
text
Body
<p>I try to create 4 child processes who will work simultaneously, but the output of my program is quite random: sometimes one of the processes is not created (the printf statement is not executed). I can not understand the reason for this, because when I use the wait() function in my parent it should wait for it's children to finish? Here is my code:</p> <pre><code>#include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <sys/types.h> #define NR_OF_PROCESSES 4 void readProcess(void); void tokenProcess(void); void calculatorProcess(void); void errorProcess(void); void (*functionTable[NR_OF_PROCESSES]) (void) = {readProcess, tokenProcess, calculatorProcess, errorProcess}; int main(void) { int i; int status; for (i = 0; i < NR_OF_PROCESSES; i++) { int pid = fork(); if (pid < 0) { perror("could not fork"); return 0; } if (pid == 0) { functionTable[i](); exit(0); } } printf("parent is waiting"); wait(status); return (0); } void readProcess(void) { printf("readprocess running, PID=%d, PPID=%d\n",getpid(),getppid()); } void tokenProcess(void) { printf("tokenprocess running, PID=%d, PPID=%d\n",getpid(),getppid()); } void calculatorProcess(void) { printf("calculatorprocess running, PID=%d, PPID=%d\n",getpid(),getppid()); } void errorProcess(void) { printf("errorprocess running, PID=%d, PPID=%d\n",getpid(),getppid()); } </code></pre> <p>Also, I want to add interprocess communication with pipes later on. Will this be possible if I implement the processes this way? Any better solution?</p>
Tags
<c><process><fork><function-pointers>
Title
parent doesn't create child?
singulars
PostAcceptedAnswerId
1. PO
  singulars
  PostTypePostTypeId
  PTAnswer
PostParentId
1. This table or related slice is empty.
PostTypePostTypeId
1. PTQuestion
UserLastEditorUserId
1. USTono
UserOwnerUserId
1. USTono
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. PO
  singulars
  PostTypePostTypeId
  PTAnswer
VotesPostIdCreationDate
1. VO
  singulars
  PostPostId
  POparent doesn't create child?
  UserUserId
  This table or related slice is empty.
  VoteTypeVoteTypeId
  VTClose
2. VO
  singulars
  PostPostId
  POparent doesn't create child?
  UserUserId
  This table or related slice is empty.
  VoteTypeVoteTypeId
  VTUpMod
3. VO
  singulars
  PostPostId
  POparent doesn't create child?
  UserUserId
  This table or related slice is empty.
  VoteTypeVoteTypeId
  VTClose
CommentsPostId

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