Anyone know how cksum works? Post: 57429

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Top Forums Shell Programming and Scripting Anyone know how cksum works? Post 57429 by kapolani on Wednesday 27th of October 2004 02:06:19 PM

10-27-2004

Registered User

Anyone know how cksum works?

hello all.

I'm not asking about the algorithm - or how it goes about computing the checksum - I'm asking how it views/looks at the files it does the cksum on.

For instance:

Say you had a directory named "dir_A"

And within this directory you had some files.

So:

dir_A
- file1
- file2
- file3

Do you have to step through dir_A and compute a cksum for EACH individual file?

For instance:

% cd dir_A
% cksum file1
% return some number
% cksum file2
% return some number
% cksum file3
% return some number

Or, can I just compute the cksum for the whole directory?

For instance:

% cksum dir_A
% return some number

If one of the files within dir_A changes and I redo the cksum is it safe to say that a valid cksum will be computed for the whole directory? What if file1 WITHIN dir_A changed - will the cksum change?

Or, do you have to compute a cksum for each individual file?

Thanks!!!

kapolani

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LEARN ABOUT DEBIAN

shishi_safe_cksum

shishi_safe_cksum(3)						      shishi						      shishi_safe_cksum(3)

NAME

       shishi_safe_cksum - API function

SYNOPSIS

       #include <shishi.h>

       int shishi_safe_cksum(Shishi * handle, Shishi_asn1 safe, int32_t * cksumtype, char ** cksum, size_t * cksumlen);

ARGUMENTS

       Shishi * handle
		   shishi handle as allocated by shishi_init().

       Shishi_asn1 safe
		   safe as allocated by shishi_safe().

       int32_t * cksumtype
		   output checksum type.

       char ** cksum
		   output array with newly allocated checksum data from SAFE.

       size_t * cksumlen
		   output size of output checksum data buffer.

DESCRIPTION

       Read checksum value from KRB-SAFE.  cksum is allocated by this function, and it is the responsibility of caller to deallocate it.

RETURN VALUE

       Returns SHISHI_OK iff successful.

REPORTING BUGS

       Report bugs to <bug-shishi@gnu.org>.

COPYRIGHT

       Copyright (C) 2002-2010 Simon Josefsson.
       Copying	and  distribution  of  this file, with or without modification, are permitted in any medium without royalty provided the copyright
       notice and this notice are preserved.

SEE ALSO

       The full documentation for shishi is maintained as a Texinfo manual.  If the info and shishi programs are properly installed at your  site,
       the command

	      info shishi

       should give you access to the complete manual.

shishi								       1.0.1						      shishi_safe_cksum(3)