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Full Discussion: Declare member of struct as a pointer in c
Top Forums Programming Declare member of struct as a pointer in c Post 302714121 by chap on Thursday 11th of October 2012 08:32:21 PM
Old 10-11-2012
Declare member of struct as a pointer in c
I have a uint8_t *C = malloc(24*sizeof(uint8_t));

I need to send some integers and this *C to another node(in ad hoc network). So I am going to use a struct

Code:
` struct fulMsg { 
int msgType; 
int msgCount; 
//uint8_t *CC;
} fulMsg_t;

typedef struct fulMsg fulMsg_tt;`

there is a method called
Code:
 packetbuf_copyfrom(X, sizeof(X));

in my api(contiki). If I create struct like this
Code:
struct fulMsg *fmsg = &fulMsg_t;

I can use the above method like this
Code:
packetbuf_copyfrom(fmsg, 8);

and from the other end I can easily get those two values.

So my problem is when I am going to apply same thing to that pointer it is not working the network simulator that I am using suddenly be crashed (I think there is a segmentation fault). I can't initialize size of *C in the struct no. And how correctly do this fmsg->CC = C;

At the other end this is how I receive this struct is
Code:
struct fulMsg *r_fmsg = &fulMsg_t;

and
Code:
rfmsg = (fulMsg_tt *)(packetbuf_dataptr());

. So I can easily get values from other end. (No need to do ntoh and hton, but it is ok if this really needs that)

In simple what I want to do is send the value of *C contain and some other integers to another node. How can I correctly do this.

related question post by me regarding this project Segmentation fault when debugging in C
Thanks
 

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LEARN ABOUT OSX

locale::codes::langext

Locale::Codes::LangExt(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangExt(3pm)

NAME

       Locale::Codes::LangExt - standard codes for language extension identification

SYNOPSIS

	  use Locale::Codes::LangExt;

	  $lext = code2langext('acm');		       # $lext gets 'Mesopotamian Arabic'
	  $code = langext2code('Mesopotamian Arabic'); # $code gets 'acm'

	  @codes   = all_langext_codes();
	  @names   = all_langext_names();

DESCRIPTION

       The "Locale::Codes::LangExt" module provides access to standard codes used for identifying language extensions, such as those as defined in
       the IANA language registry.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default IANA language
       registry codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying language extensions. A code set may be specified using either a name, or
       a constant that is automatically exported by this module.

       For example, the two are equivalent:

	  $lext = code2langext('acm','alpha');
	  $lext = code2langext('acm',LOCALE_LANGEXT_ALPHA);

       The codesets currently supported are:

       alpha
	   This is the set of three-letter (lowercase) codes from the IANA language registry, such as 'acm' for Mesopotamian Arabic.

	   This is the default code set.

ROUTINES

       code2langext ( CODE [,CODESET] )
       langext2code ( NAME [,CODESET] )
       langext_code2code ( CODE ,CODESET ,CODESET2 )
       all_langext_codes ( [CODESET] )
       all_langext_names ( [CODESET] )
       Locale::Codes::LangExt::rename_langext  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::LangExt::add_langext  ( CODE ,NAME [,CODESET] )
       Locale::Codes::LangExt::delete_langext  ( CODE [,CODESET] )
       Locale::Codes::LangExt::add_langext_alias  ( NAME ,NEW_NAME )
       Locale::Codes::LangExt::delete_langext_alias  ( NAME )
       Locale::Codes::LangExt::rename_langext_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangExt::add_langext_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangExt::delete_langext_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.iana.org/assignments/language-subtag-registry
	   The IANA language subtag registry.

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 2011-2012 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.16.2							    2012-10-11					       Locale::Codes::LangExt(3pm)
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