Reading stored function pointer

[gtok]

I need help on how to read and reset a value which points to a function here is an example on what i need


//this is what i have now that sets up a global variable
void setfunctionaddress(void (*myfuncaddress)(void))
{
workarea[selected]->data = myfunctionaddress
}

void firstfunction(void)
{
do something
}

void secondfunction(void)
{
do something new
}

//start of example
//#1 i need to setup setfunctionaddress
//#2 need to be able to read/save address what is stored
//#3 need to set setfunctionaddress to new value
//#4 neet to reset setfunctonaddress back from read/save
main()
{
setfunctionaddress(firstfunction);
jumptofunction();
}
void jumptofunction(void)
{
//this is what i need to do
//READ what is stored at setfunctionaddress
setfunctionaddress(secondfunction);
do something
//RESET setfunctionaddress to what was READ
return;
}

 

[Guest_imported]

fried,

i have used your template , now you may manipulate
this program the way you like to achieve what you desire


#include <stdio.h>

typedef void (*funcPtr)();

funcPtr lpFunc[10]={0};//assuming 10 function ptr stored
int currentNo=0;

void setfunctionaddress(/* funcPtr */ void (*myfunctionaddress)() )
{
if(currentNo<10)
lpFunc[currentNo++]= myfunctionaddress;
else
printf(&quot;no more addresses can be accomodated\n&quot;
}

void firstfunction(void)
{
printf(&quot;am in the first function\n&quot;
}

void secondfunction(void)
{
printf(&quot;am in the second function\n&quot;
}


//start of example
//#1 i need to setup setfunctionaddress
//#2 need to be able to read/save address what is stored
//#3 need to set setfunctionaddress to new value
//#4 neet to reset setfunctonaddress back from read/save

void jumptofunction(void)
{
//this is what i need to do
//READ what is stored at setfunctionaddress
int x=0;
while(x<currentNo)
{
(lpFunc[x++])();
}



// do something
//RESET setfunctionaddress to what was READ
// return;
}
void main()
{
setfunctionaddress(firstfunction);
setfunctionaddress(secondfunction);

jumptofunction();
}

hope this helps

bye
yogesh

 

[Guest_imported]

yogesh,

in this way is it possible to simulate run time polymorphism as we have in cpp

manohar