sleep.3 (1150B)
1 .TH SLEEP 3 2 .SH NAME 3 sleep, alarm \- delay, ask for delayed note 4 .SH SYNOPSIS 5 .B #include <u.h> 6 .br 7 .B #include <libc.h> 8 .PP 9 .B 10 int sleep(long millisecs) 11 .PP 12 .B 13 long alarm(unsigned long millisecs) 14 .SH DESCRIPTION 15 .I Sleep 16 suspends the current process for the number 17 of milliseconds specified by the argument. 18 The actual suspension time may be a little more or less than 19 the requested time. If 20 .I millisecs 21 is 0, the process 22 gives up the CPU if another process is waiting to run, returning 23 immediately if not. 24 Sleep returns \-1 if interrupted, 0 otherwise. 25 .PP 26 .I Alarm 27 causes an 28 .B alarm 29 note (see 30 .MR notify (3) ) 31 to be sent to the invoking process after the number of milliseconds 32 given by the argument. 33 Successive calls to 34 .I alarm 35 reset the alarm clock. 36 A zero argument clears the alarm. 37 The return value is the amount of time previously remaining in 38 the alarm clock. 39 .SH SOURCE 40 .B \*9/src/lib9/sleep.c 41 .SH SEE ALSO 42 .MR intro (3) 43 .SH DIAGNOSTICS 44 These functions set 45 .IR errstr . 46 .SH BUGS 47 To avoid name conflicts with the underlying system, 48 .I sleep 49 and 50 .I alarm 51 are preprocessor macros defined as 52 .I p9sleep 53 and 54 .IR p9alarm ; 55 see 56 .MR intro (3) .