olegsp
asked on
The size of available memory
I have a loop which essentially looks like:
for(i=0; i<imax; i++)
{
fscanf(inputfile,"%d",&dat
data_pointer[i]=new char[data_size]; // line 2
}
It is quite possible that at some point the system may run out of memory, failing to allocate whatever is needed in line 2. I want to predict this failure. Is there a way to find the potentially available memory size right after line 1 so that line 2 can be avoided if memory is too low ?
(Certainly I can preset data_pointer to NULL, and see if it changed in line 2 - but this happens after the allocation failure, with Windows "Out of memory" box already on my screen)
for(i=0; i<imax; i++)
{
fscanf(inputfile,"%d",&dat
data_pointer[i]=new char[data_size]; // line 2
}
It is quite possible that at some point the system may run out of memory, failing to allocate whatever is needed in line 2. I want to predict this failure. Is there a way to find the potentially available memory size right after line 1 so that line 2 can be avoided if memory is too low ?
(Certainly I can preset data_pointer to NULL, and see if it changed in line 2 - but this happens after the allocation failure, with Windows "Out of memory" box already on my screen)
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ASKER
OK, this helped. Since I was not using MFC in this particular code, I rewrote it as
try
{data_pointer[i]=new char [data_size];
}
catch (...) // catch all exceptions
{
//New failed to allocate space - at a minimum get out of for loop
break;
}
Do you know, in C++ terms, what type of exception I am supposed to catch (i.e., what C++ exception corresponds to CMemoryException in MFC) ? Do I need to clean up anything (I believe e->Delete() must appear in your catch block) ?
try
{data_pointer[i]=new char [data_size];
}
catch (...) // catch all exceptions
{
//New failed to allocate space - at a minimum get out of for loop
break;
}
Do you know, in C++ terms, what type of exception I am supposed to catch (i.e., what C++ exception corresponds to CMemoryException in MFC) ? Do I need to clean up anything (I believe e->Delete() must appear in your catch block) ?
Yes, you definitely need to call
e->Delete();
The reason is because one doesn't know where the object was allocated (could be global,local or on heap). e->Delete() looks at an internally maintanined variable to make the determination of what to do with the object.
I believe that outside of MFC to catch a new error you need to call
set_new_handler("Your new handler function address").
Glenn
e->Delete();
The reason is because one doesn't know where the object was allocated (could be global,local or on heap). e->Delete() looks at an internally maintanined variable to make the determination of what to do with the object.
I believe that outside of MFC to catch a new error you need to call
set_new_handler("Your new handler function address").
Glenn
ASKER
Thanks.
ASKER