>Thanks for your input, Peter. Actually you're right, the app running as a service frees memory but in a strange way: it doesn't immediately give it out to the pool but when another service needs memory it is released to a certain extent so as it can be "torn off by the crowd". What I'm afraid of is that some programs may not know if that partly released memory (or signed to future release) is for reuse...
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>I don't understand why the memory is not released immediately. While I've scanned a text file and FCLOSED it the memory should be returned to the pool which is not the case at all.
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>Przemek

Your are sure entitled to feel the danger :
Under NT4 start a FPDos-app when some other tasks are running;
Chance is hight that the new app won't get enough memory. However, once NT detects this, it gets prepared to expand the memory to the swap-file. But not for this app ! So 100 % guaranteed is to quit the app and start it again ... now it's fine. This is NT4's memory manager (W95 is even worse).