on my desktop i am using the kde rotating desktop image option. this rotates images randomly every half hour. now, i would like to write an html file which will have an inline frame with some text, maybe system messages, or my friends live journal thati read alot, or unix.com! however, i dont want... (1 Reply)
Hi,
From some time, we have noticed that our ascii files have started corrupting due to the presence of some random control characters (^@, ^M, ^H, ^D). The characters appear randomly on any file after the process that creates the file finishes. If we rerun the process, the files re creates... (0 Replies)
I want to take the below data, and have it output to file only the STMC#/(IP address) and the "there are X number of updates to install" lines for each machine. I know it's easy, but Im a beginner in BASH stuff, my solution would probably take way too many lines to do something easy.Thanks!
... (5 Replies)
Hi there, I have a text file with several colums separated by "|;#" I need to search the file extracting all columns starting with the value of "1" or "2" saving in a separate file just the first 7 columns of each row maching the criteria, with replacement of the saparators in the nearly created... (4 Replies)
i have a file in following format
1 32 3
4 6 4
4 45 1
45 4 61
54 66 4
5 65 51
56 65 1
12 32 85
now here the total number of lines are 8(they vary each time)
Now i want to select only those lines in which the values... (6 Replies)
What I have are two text files that I need to shuffle randomly, but I need the two files to be randomly shuffled the same way. I have heard of shuf but I do not know how to use it for two files. Maybe there is also an easy/simple awk command I do not know about that could handle this problem.
... (3 Replies)
Hello,
This is my code:
nb_lignes=`wc -l $1 | cut -d " " -f1`
for i in $(seq $nb_lignes)
do
m=`head $1 -n $i | tail -1`
//command
done
Please how can i change it to get Get 20% of lines in File randomly to apply "command" on each line ? 20% or 40% or 60 % (it's a parameter)
Thank you. (15 Replies)
Hi
I need to select lines from a txt file, I have got a line starting with ZMIO:MSISDN= and after a few line I have another line starting with 'MOBILE STATION ISDN NUMBER' and another one starting with 'VLR-ADDRESS' I need to copy these three lines as three different columns in a separate... (3 Replies)
Dear Folks
I have one column of 15000 lines and want to select randomly 5000 of them in five different times without replacement. I am aware that command 'shuf' and 'sort -R' could select randomly those lines but I am not sure how could I avoid the replacement of selection line. Does anyone have... (10 Replies)
hi all,
trying this using shell/bash with sed/awk/grep
I have two files, one containing one column, the other containing multiple columns (comma delimited).
file1.txt
abc12345
def12345
ghi54321
...
file2.txt
abc1,text1,texta
abc,text2,textb
def123,text3,textc
gh,text4,textd... (6 Replies)
Discussion started by: shogun1970
6 Replies
LEARN ABOUT SUSE
srand
RAND(3) Linux Programmer's Manual RAND(3)NAME
rand, rand_r, srand - pseudo-random number generator
SYNOPSIS
#include <stdlib.h>
int rand(void);
int rand_r(unsigned int *seedp);
void srand(unsigned int seed);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
rand_r(): _POSIX_C_SOURCE >= 1 || _XOPEN_SOURCE || _POSIX_SOURCE
DESCRIPTION
The rand() function returns a pseudo-random integer in the range [0, RAND_MAX].
The srand() function sets its argument as the seed for a new sequence of pseudo-random integers to be returned by rand(). These sequences
are repeatable by calling srand() with the same seed value.
If no seed value is provided, the rand() function is automatically seeded with a value of 1.
The function rand() is not reentrant or thread-safe, since it uses hidden state that is modified on each call. This might just be the seed
value to be used by the next call, or it might be something more elaborate. In order to get reproducible behavior in a threaded applica-
tion, this state must be made explicit. The function rand_r() is supplied with a pointer to an unsigned int, to be used as state. This is
a very small amount of state, so this function will be a weak pseudo-random generator. Try drand48_r(3) instead.
RETURN VALUE
The rand() and rand_r() functions return a value between 0 and RAND_MAX. The srand() function returns no value.
CONFORMING TO
The functions rand() and srand() conform to SVr4, 4.3BSD, C89, C99, POSIX.1-2001. The function rand_r() is from POSIX.1-2001.
POSIX.1-2008 marks rand_r() as obsolete.
NOTES
The versions of rand() and srand() in the Linux C Library use the same random number generator as random(3) and srandom(3), so the lower-
order bits should be as random as the higher-order bits. However, on older rand() implementations, and on current implementations on dif-
ferent systems, the lower-order bits are much less random than the higher-order bits. Do not use this function in applications intended to
be portable when good randomness is needed. (Use random(3) instead.)
EXAMPLE
POSIX.1-2001 gives the following example of an implementation of rand() and srand(), possibly useful when one needs the same sequence on
two different machines.
static unsigned long next = 1;
/* RAND_MAX assumed to be 32767 */
int myrand(void) {
next = next * 1103515245 + 12345;
return((unsigned)(next/65536) % 32768);
}
void mysrand(unsigned seed) {
next = seed;
}
SEE ALSO drand48(3), random(3)COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2008-08-29 RAND(3)