What's a system call ( Was: 'what' doesn't use perror...)

[Chris Lakewood]

In article <913 at twwells.uucp] bill at twwells.UUCP (T. William Wells) writes:
]And then consider sleep(). I know of one system where sleep was
]implemented as a system call (and documented in section 2) because
]the standard version of sleep would hang occasionally. Consider:
]
]	alarm(n);
]	pause();
]
](the guts of sleep) and what happens if the process doesn't run for n
]seconds. Have you ever had tail hang on a heavily loaded system? (I
]have.) Guess why.
]---
]Bill                            { uunet | novavax } !twwells!bill

Don't leave us in suspense...  What happens if the process doesn't run for
n seconds?  Actually, the process won't run for at least n seconds unless
it receives some signal.  The pause causes the process to block until a
signal is received.