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Full Discussion: UNIX Message Queue
Top Forums Programming UNIX Message Queue Post 302270233 by qlyine on Saturday 20th of December 2008 08:27:57 AM
Old 12-20-2008
UNIX Message Queue

Hello !!!!! I have a simple question but i can't find the answer anywhere hope to meet it here.

Why it is a bad idea to pass pointers through message queues ?
Most structs i see all of their char types are arrays... Is it becase having pointers means we could possibily send wrong bytes ?
For instances :

typedef struct {
int mtype; // 4 Bytes
char *text // 1Bytes
} bufferA;

typedef struct {
int mtype; // 4 Bytes
char text[10]; // 10Bytes
} bufferB;

On both structs text is "Hello World\0", on bufferA we would only send 1Byte which maybe means we would only send H while on bufferB we would send the whole sentence, "Hello World" . Is that correct ?
 

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eXosip2 request outside of dialog(3)				    libeXosip2				      eXosip2 request outside of dialog(3)

NAME
eXosip2 request outside of dialog - Functions int eXosip_message_build_request (osip_message_t **message, const char *method, const char *to, const char *from, const char *route) int eXosip_message_send_request (osip_message_t *message) int eXosip_message_build_answer (int tid, int status, osip_message_t **answer) int eXosip_message_send_answer (int tid, int status, osip_message_t *answer) Detailed Description Function Documentation int eXosip_message_build_request (osip_message_t **message, const char *method, const char *to, const char *from, const char *route) Build a default request message. This method will be updated to send any message outside of dialog In this later case, you'll specify the method to use in the second argument. Parameters: message Pointer for the SIP request to build. method request method. (like 'MESSAGE' or 'PING'...) to SIP url for callee. from SIP url for caller. route Route header for request. (optional) int eXosip_message_send_request (osip_message_t *message) Send an request. Parameters: message SIP request to send. int eXosip_message_build_answer (inttid, intstatus, osip_message_t **answer) Build answer for a request. Parameters: tid id of transaction. status status for SIP answer to build. answer The SIP answer to build. int eXosip_message_send_answer (inttid, intstatus, osip_message_t *answer) Send answer for a request. Parameters: tid id of transaction. status status for SIP answer to send. answer The SIP answer to send. (default will be sent if NULL) Author Generated automatically by Doxygen for libeXosip2 from the source code. Version 3.1.0 Sun Jun 24 2012 eXosip2 request outside of dialog(3)
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