Something I've discovered through (painful) experience is that threadedprograms cannot portably fork() in one thread and then wait() forthe forked process in another one.

This will work in some environments but fail explosively in others; theone I stubbed my toe on was a Linux 2.4 kernel based system (without NPTL , which is the usual state of affairsfor 2.4-based Linux distributions).

Admittedly, mixing threads and fork() is a bit perverse, butsometimes it

Presented in the traditional illustrated form:

; dig +short ns hinet.net.tw.reg.hinet.net.tw.www.hinet.net.tw.hinet.net.tw.

This looks good, except for the fact that they all have the sameIP address, 210.65.1.231. You would think that a large TaiwaneseISP would be able to afford more than one DNS server, but perhapsthey're too busy beefing up their network

This one is a close variation of HowNotToDoDNSIX , but it earns extrapoints for making the reverse error from a common one. Presented insemi-illustrated format:

; dig +short ns system-bank.net.dns01.system-bank.net.dns02.system-bank.net.

(At this point I will pause to note that dns01.system-bank.net anddns02.system-bank.net have the same IP address, 218

Most new products are upgrades of old ones. I don't mean in the senseof upgrade sales (although that too), but in terms of the code they'rebuilt from; they are revisions of existing codebases, not freshlywritten from scratch.

This has extremely rational economic and developmentreasons, as articulated by Joel Spolsky amongothers; there is a lot of money and value in existing codebases. Butignoring all the arguments about cost and captured knowledge and soon, there's another big reason