Help with typedef struct

[TnGraham]

Hey,
I am working on converting C++ code from Visual Studio 6.0 to Visual Studio 2010. I have came upon the following code and don't fully understand:

typedef struct st_l16 s_l16;

typedef struct st_l16
{
 declared varables are here
}; 

In another file the following code exists:

num = s_l16->host_nav_data.platform_lat;//Once in VS 2010 I get an error for this stating thast s_l16 is undeclared, but no error in VS 6.0 

Any help will be greatly appreciated!!
Thanks In Advance!!

[webJose]

Beats me. according to the typedef, s_116 is a type and therefore cannot be applied operator->. Unless VS 2010 wants you to declare the struct first? Try that.

BTW, the struct declaration is incomplete. It lacks a name at the end. Personally I would merge the 2 like this:

typedef struct st_116
{
    ....
} s_116;

[Galik]

In C++ you don't need to typedef your struct. This is sufficient:

struct st_l16
{
    //declared varables are here
}; 

Using typedef struct is a hangover from C where it was necessary if you wanted to avoid typing keyword struct all the time.

You code doesn't make much sense to me. s_l16 is declared as a type and then later used as a variable...?

[zb0S216C]

I use type-defined structs most of the time. It's best to read upon typedef to understand what's truly happening. In C++, type-defined structs don't affect the code, so type-defining structs is theoretically a personal preference.

References:
^[1]http://publib.boulder.ibm.com/infocenter/lnxpcomp/v7v91/index.jsp?topic=%2Fcom.ibm.vacpp7l.doc%2Flanguage%2Fref%2Fclrc03typdef.htm

_Wazzak