rcmcs@ctihf:/ora2/rcmcs/tmp > man srand
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C Library Functions rand(3C)
NAME
rand, srand, rand_r - simple random-number generator
SYNOPSIS
#include <stdlib.h>
int rand(void);
void srand(unsigned int seed);
int rand_r(unsigned int *seed);
DESCRIPTION
The rand() function uses a multiplicative congruential
random-number generator with period 2**32 that returns suc-
cessive pseudo-random numbers in the range of 0 to RAND_MAX
(defined in <stdlib.h>).
The srand() function uses the argument seed as a seed for a
new sequence of pseudo-random numbers to be returned by sub-
sequent calls to rand(). If srand() is then called with the
same seed value, the sequence of pseudo-random numbers will
be repeated. If rand() is called before any calls to
srand() have been made, the same sequence will be generated
as when srand() is first called with a seed value of 1.
The rand_r() function has the same functionality as rand()
except that a pointer to a seed seed must be supplied by
the caller. The seed to be supplied is not the same seed as
in srand().
rcmcs@ctihf:/ora2/rcmcs/tmp > man time
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User Commands time(1)
NAME
time - time a simple command
SYNOPSIS
time [ -p ] utility [ argument. .. ]
DESCRIPTION
The time utility invokes utility operand with argument, and
writes a message to standard error that lists timing statis-
tics for utility. The message includes the following infor-
mation:
o The elapsed (real) time between invocation of utility
and its termination.
o The User CPU time, equivalent to the sum of the
tms_utime and tms_cutime fields returned by the
times(2) function for the process in which utility is
executed.
o The System CPU time, equivalent to the sum of the
tms_stime and tms_cstime fields returned by the
times() function for the process in which utility is
executed.
When time is used as part of a pipeline, the times reported
are unspecified, except when it is the sole command within a
grouping command in that pipeline. For example, the commands
on the left are unspecified; those on the right report on
utilities a and c, respectively.
time a | b | c { time a } | b | c
a | b | time c a | b | (time c)
OPTIONS
The following option is supported:
-p Write the timing output to standard error in the
following format: