c - Error in msgrcv: Invalid Arguments -

-

I am writing a code on a UNIX system in C. I have created a message queue server every time I get a new message I The fork and baby process handles the new customer. The server waits for the new customer here is the code. 

  for (;;) {struct my_msgbuf buf; If (MSGRCV (MScDID, and (BF.M.T.P.), Size (BF), 1, 0) == -1) Peer ("MSGRCV"); If ((pid = fork ()) <0) false ("fork"); If (pid == 0) {// child code}} now code works for the first time, but msgrcv returns the following error on the second visit - msgrcv: invalid instead Argument is waiting for new messages.   
 
 
  MSGRCV  a  msgsz  parameter, but it It is not the size of a  struct my_msgbuf ; rather, it is the number of bytes in the  mtext []  area of ​​the structure. 
 
 You are not really going to use  struct msgbuf , I think it would be normal to define your own with the appropriate place. You have this method, your  Buf  declaration allocates only 1 byte, and then the code tells the kernel that you have  sizeof buf  bytes, which you do not. As a result, the code is called to call  undefined behavior  or UB. 
 
 This can not be understood by  EINVAL , but one must always correct known bugs and retest because UB taints further analysis ...

Comments

Post a Comment

Popular posts from this blog

ios - Form Sheet content disappearing -

-
Image
I am trying to apply a form sheet. Looks like this on the storyboard: App background only when I run Appears and everything else is hidden. I am presenting a form sheet using model sheets - I am working with the form sheet and I (WREGLR Regular) size. Why is this happening?
Read more

MySql variables and php -

-
I am getting an error with php in order to format mysql_query () in php to format this string What is the right way? SELECT SELECT SELECT (*) Agents @AgentCount; User_Agent_English, User_Angent_Oursal, US.___Gent_Aginal, COUNT (User_Agent_Percade) ACC, COUNT (*) / (AgentCount) Percentage by agents user_agent_preser order DEC limit limit 50; In PHP, how am i setting $ query $ query = "SELECT count (*) agents @ agentcount; SELECT user_agent_parsed, User_agent_original , COUNT (user_agent_parsed) ascount, COUNT (*) / (@AgentCount) as a percentage by user_agent_parced by URI date DESC limit 50 "; This exact query will work properly if I put it in MySQL directly through a command line session. Do I need to release two separate php calls from mysql_query () and store the results first? I get the following error: There is an error in your SQL syntax; Instead of using a sub-selection and instead of using the 'SELECT user_agent_parsed, user_agent_original, ne...
Read more

php - Laravel - Overriding a resource route into a different route filter group -

-
Does Laravel's routing work as expected? What I think, if I want to override a route, then I just have to give the expected route before each other. I have something like this: root :: group (array ('first' = & gt; 'defaultLoads' =); function () {root :: post 'Newsletter', 'newsletter controller @ store'); root: group (array ('(newsletter', 'newsletter controller');}}); That if I post this route, only http://domain.com/newsletter should run only the default loads route filter. However, when I call php Runs artisan routes , I get this: | | POST newsletter | newsletter.store | newslettercontroller@ store | default loads | login | | though it reads the route correctly (PHP artisan loads which The correct path is to the right place) but the file of the resource path even if it is not in the filter group, the path is affected. Then my question: How does it work Laravel? If so, do I post this -> Newsle...
Read more