Re: std:: vector push_back a struct
On Dec 18, 12:59 pm, jmsanchezdiaz <jmsanchezd...@gmail.com> wrote:
On 13 dic, 21:41, "Daniel T." <danie...@earthlink.net> wrote:
jmsanchezdiaz <jmsanchezd...@gmail.com> wrote:
I explain my question with more detail:
I have a:
typedef struct
{
CnovaMsgTypes id; // packet type identificat=
or
char* data; //data of the structure
} data_foto;
In a header shared with C, no doubt. Otherwise, there's no need
for the typedef, and std::string (or std::vector<char>) would
doubtlessly be preferable to the char*. Also, you haven't shown
us the type of id. That could be important.
vector< vector< data_foto > >vector_fotos;
And I want to access the fields of the struct for doing an
assignement in a case. I do this in a piece of my code:
switch(pfc[j].id)
{
case CONTROL_HV:
addPacketToSendBuffer( CONTROL_HV, 0, sizeof(T_ControlHV),=
(char *)
&h2pcnova->h2ig.cnt );
if (take_foto)
{
vector_fotos[minuto_actual][(int)(pfc[j].id)].id =
pfc[j].id;
vector_fotos[minuto_actual][(int)(pfc[j].id)].data
= (char*)&(h2pcnova->h2ig.cnt);
}
[...]
but when I debbug vector_fotos[minuto_actual] appears: "class
std::vector< data_foto, std::allocator< data_foto >&)0x0 Cannot
access"
What's the problem??
Who knows? There's no where near enough information. If it's
really a case of your dereferencing a null pointer (which is
what the error message suggests), either you have a null pointer
somewhere yourself, or one of the vectors you access is in fact
empty.
Try compiling with debug turned on for the STL and use whatever
memory checkers you have. (With g++ under Linux, this would
mean "-D_GLIBCXX_CONCEPT_CHECKS -D_GLIBCXX_DEBUG
-D_GLIBCXX_DEBUG_PEDANTIC" and valgrind, for example.)
--
James Kanze (GABI Software) email:james.kanze@gmail.com
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