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Full Discussion: generating 16 digit random number in C
Top Forums Programming generating 16 digit random number in C Post 302344140 by jim mcnamara on Friday 14th of August 2009 04:48:31 PM
Old 08-14-2009
Another thought - not all unixes have /dev/urandom and /dev/random.
You can read abou them, but they do provide a random bitstream. If your box has them (Soalris & Linux come to mind) read on -

An example of how to play with the bitstream using Corona's idea.:
Code:
#include <stdio.h>

typedef
union
{
	char tmp[sizeof(unsigned long long)];
	unsigned long long myll;
} ll_t;


unsigned long long llrand(void)
{
	FILE *in=fopen("/dev/urandom", "r");
	ll_t ll_u;
	fread(ll_u.tmp, sizeof(ll_u.tmp), 1, in);
	fclose(in);
	return ll_u.myll;
}

int main()
{
	char tmp[64]={0x0};
	char working[64]={0x0};
	int i=0;
		
	for(i=0; i< 20; i++)
	{
		while(strlen(tmp) < 16)
		{
			sprintf(working, "%lu", llrand() );
			strcat(tmp, working);
		}
		tmp[16]=0x0;
		printf("%s\n", tmp);
		*tmp=0x0;
	}
	return 0;
}

This needs work but you get the idea.
 

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LEARN ABOUT HPUX

dh_movefiles

DH_MOVEFILES(1) 						     Debhelper							   DH_MOVEFILES(1)

NAME

       dh_movefiles - move files out of debian/tmp into subpackages

SYNOPSIS

       dh_movefiles [debhelperoptions] [--sourcedir=dir] [-Xitem] [file...]

DESCRIPTION

       dh_movefiles is a debhelper program that is responsible for moving files out of debian/tmp or some other directory and into other package
       build directories. This may be useful if your package has a Makefile that installs everything into debian/tmp, and you need to break that
       up into subpackages.

       Note: dh_install is a much better program, and you are recommended to use it instead of dh_movefiles.

FILES

       debian/package.files
	   Lists the files to be moved into a package, separated by whitespace. The filenames listed should be relative to debian/tmp/. You can
	   also list directory names, and the whole directory will be moved.

OPTIONS

       --sourcedir=dir
	   Instead of moving files out of debian/tmp (the default), this option makes it move files out of some other directory. Since the entire
	   contents of the sourcedir is moved, specifying something like --sourcedir=/ is very unsafe, so to prevent mistakes, the sourcedir must
	   be a relative filename; it cannot begin with a `/'.

       -Xitem, --exclude=item
	   Exclude files that contain item anywhere in their filename from being installed.

       file ...
	   Lists files to move. The filenames listed should be relative to debian/tmp/. You can also list directory names, and the whole directory
	   will be moved. It is an error to list files here unless you use -p, -i, or -a to tell dh_movefiles which subpackage to put them in.

NOTES

       Note that files are always moved out of debian/tmp by default (even if you have instructed debhelper to use a compatibility level higher
       than one, which does not otherwise use debian/tmp for anything at all). The idea behind this is that the package that is being built can be
       told to install into debian/tmp, and then files can be moved by dh_movefiles from that directory. Any files or directories that remain are
       ignored, and get deleted by dh_clean later.

SEE ALSO

       debhelper(7)

       This program is a part of debhelper.

AUTHOR

       Joey Hess <joeyh@debian.org>

11.1.6ubuntu2							    2018-05-10							   DH_MOVEFILES(1)
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