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Full Discussion: Missing Logic Looping Through Switch Statement
Top Forums Programming Missing Logic Looping Through Switch Statement Post 303022580 by RudiC on Monday 3rd of September 2018 03:45:25 AM
Old 09-03-2018
Calling random seed repeatedly is sort of overdoing it - or, in your case, even counterproductive. Do it once at program startup - if at all necessary as the compiler / interpreter may do it for you.

I know you are compiling a (C) program. Just as a hint, man awk explicitly says
Quote:
Srand(expr) is useful for repeating pseudo random sequences.
Code:
awk 'BEGIN {srand(NULL); for (i=1; i<=10; i++) print rand()}'
0.131538
0.755605
0.45865
0.532767
0.218959
0.0470446
0.678865
0.679296
0.934693
0.383502
awk 'BEGIN { for (i=1; i<=10; i++) {srand(NULL); print rand()}}'
0.131538
0.131538
0.131538
0.131538
0.131538
0.131538
0.131538
0.131538
0.131538
0.131538

Although you are calling srand() with a sort of random parameter, the current system epoch time, the execution will be that fast epoch seconds will not change - that's why you lose the random effect.


Just remove the srand() from your function.
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LEARN ABOUT OSX

rand_r

RAND(3) 						   BSD Library Functions Manual 						   RAND(3)

NAME

     rand, rand_r, srand, sranddev -- bad random number generator

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <stdlib.h>

     int
     rand(void);

     int
     rand_r(unsigned *seed);

     void
     srand(unsigned seed);

     void
     sranddev(void);

DESCRIPTION

     These interfaces are obsoleted by random(3).

     The rand() function computes a sequence of pseudo-random integers in the range of 0 to RAND_MAX (as defined by the header file <stdlib.h>).

     The srand() function sets its argument seed as the seed for a new sequence of pseudo-random numbers to be returned by rand().  These
     sequences are repeatable by calling srand() with the same seed value.

     If no seed value is provided, the functions are automatically seeded with a value of 1.

     The sranddev() function initializes a seed, using the random(4) random number device which returns good random numbers, suitable for crypto-
     graphic use.

     The rand_r() function provides the same functionality as rand().  A pointer to the context value seed must be supplied by the caller.

SEE ALSO

     random(3), random(4)

STANDARDS

     The rand() and srand() functions conform to ISO/IEC 9899:1990 (``ISO C90'').

     The rand_r() function is as proposed in the POSIX.4a Draft #6 document.

BSD
								   May 25, 1999 							       BSD
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