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Top Forums Shell Programming and Scripting Random lines selection form a file. Post 302203962 by Perderabo on Tuesday 10th of June 2008 09:10:03 AM
Old 06-10-2008
Why don't you try it? The range of rand()*99999 is not 1-100, duplicate random numbers are possible, duplicate lines selected from your file are not possible.
 

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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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