fwrite hangs depending on buffer size. about z88dk HOT 5 CLOSED

So it's obviously the heap size:

        {
            unsigned int total, largest;
            mallinfo(&total, &largest);
            printf("Heap size %u largest block %u\n",total, largest);
        }

Heap size 30045 largest block 30045 bdos 59398
8192 bytes read
8192 bytes write
Heap size 21851 largest block 21851 bdos 59398
8192 bytes read
8192 bytes write
Heap size 13657 largest block 13657 bdos 59398
8192 bytes read
8192 bytes write
Heap size 5463 largest block 5463 bdos 59398
out of memory

By default it's meant to use 3/4 of the free memory between _bss_tail to the stack pointer. It's obviously not, and the override to set the top of the heap isn't working either.

I'll sort it out.

from z88dk.

It's weird that it's leaking memory as I'm using the same buffer over and over. Another program I have (much more code) hangs using even 1024 buffer. I'll wait until you identify root cause and push fix and test again. Thanks so much for fixing this stuff.

from z88dk.

You're allocating a buffer in main and inside readAndWriteFile which is inside the loop

I didn't spot the one outside initially and I've been chasing down a missing 8k of memory. Doh!

So yeah, the problem with this test case is the memory leak!

from z88dk.

I botched that, hold on, let me fix...

from z88dk.

My bad, let me close this out and get you a real example from a larger app with bdos calls, etc. Anyways, that was a z88dk hacker rank test, hahahaha

from z88dk.