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Top Forums Programming Using pointers to struct members as args to functions Post 302542817 by uiop44 on Thursday 28th of July 2011 04:31:04 PM
Old 07-28-2011
Quote:
Originally Posted by JohnGraham

Code:
/* `const' is useless here! */
struct kelly {
    /* ... */
    void (*lg)(int);
};

JohnGraham: Would const be useful if the struct was as follows?

Code:
const struct kelly {
/* ... */
void (*lg)(int);
} friends[] = {
/* ... */
};

Shamrock: Many thanks.

The "kelly" struct is based on real code that works well, but I (sloppily) took it out of a reasonably complex context, where the function being called by dereferencing "lg" varies based on the program name, whether input is from stdin/file, the command line arguments, sanity checks, etc.

To understand this code, there's a fair amount of indirection to resolve. The reward if I can figure it out is that it's a workable example of how to parse an above average number of command line variations.
 

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eX_setup.h(3)							    libeXosip2							     eX_setup.h(3)

NAME
eX_setup.h - eXosip setup API SYNOPSIS
#include <eXosip2/eXosip.h> #include <osipparser2/osip_message.h> #include <time.h> Functions int eXosip_init (void) void eXosip_quit (void) int eXosip_execute (void) int eXosip_set_option (int opt, const void *value) int eXosip_lock (void) int eXosip_unlock (void) struct osip_naptr * eXosip_dnsutils_naptr (const char *domain, const char *protocol, const char *transport, int keep_in_cache) int eXosip_dnsutils_dns_process (struct osip_naptr *output_record, int force) int eXosip_dnsutils_rotate_srv (struct osip_srv_record *output_record) int eXosip_listen_addr (int transport, const char *addr, int port, int family, int secure) int eXosip_set_socket (int transport, int socket, int port) void eXosip_set_user_agent (const char *user_agent) const char * eXosip_get_version (void) int eXosip_set_cbsip_message (CbSipCallback cbsipCallback) void eXosip_enable_ipv6 (int ipv6_enable) void eXosip_masquerade_contact (const char *public_address, int port) int eXosip_find_free_port (int free_port, int transport) int eXosip_transport_set (osip_message_t *msg, const char *transport) int eXosip_guess_localip (int family, char *address, int size) Detailed Description eXosip setup API This file provide the API needed to setup and configure the SIP endpoint. Author Generated automatically by Doxygen for libeXosip2 from the source code. Version 3.1.0 Sun Jun 24 2012 eX_setup.h(3)
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