Some troubleshooting and debugging tools show numbers in hex and some in decimal even for things that are traditionally hex, for example PID and TID. Then, when getting data from one program we need to convert it to a different base for another tool. So over some time it is possible to get an idea of what hex numbers usually are even if they don't have hexadecimal 'A'-'F' in their digits. For example, in one log we got this output:
Parent changed to 393954
Although this number is a valid hex number as well as a decimal we had the intuitive feeling that it was decimal... Checking source code of the tool revealed that it was output as decimal indeed.