See the "man" page for the unix "cksum" command.
This command outputs the fields in the following order:
Try it.
Then uses the unix Shell redirect ">" to write the output from the command to your log file (after possibly using the "awk" or "cut" commands to change the order of the output).
The question suggests the order of field output from the old unix "sum" command but the file size in this case would be in 512 byte blocks. The unix "cksum" command is much preferred to the unix "sum" command and the unix "cksum" command picks up simple transposition which the old unix "sum" command misses.
Last edited by methyl; 12-06-2011 at 05:44 PM..
Reason: addenda and typos and layout
I am spooling a text file to printer under Sun Solaris m/c (solaris 7). I want to know which directory the spooled text file is stored before it goes to printer.
B'se my main problem is to find the escape sequence from the
text file to get landscape orientation. Now when ever I spool a file... (1 Reply)
i have a file myfile. it has the below entries
/temp/firstfile
/temp/secondfile
and many more..
okay, now, i want to addup all the space occupied by this file
hmmm, but i met with a problem in getting each file out.
i did a silly command like more myfile | grep temp | ls -ltr
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Hi ,
Please help with the following questions
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Any other better suggeastions ?
2) how do I use mv command for moving the file ? I need the syntax with some examples
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find . \! -type p -exec cksum {} \; >> check.out
Okay i was able to get the checksum of the files of the directory and sub directories..how do I get the list with the checksum and the file permissions and dates in the same file...now this is driving me crazy...can anyone help me with this ? ls... (3 Replies)
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The Spooled file content is properly being displayed in UNIX.
See Example below :
ID|FILENAME |ABCDEF_DT |PROCESSED_DT |STATUS... (4 Replies)
hi all i want a script to FTP a file and should generate a quality checksum file
means when I FTP a file from one server to another server it should generate a QC file which should contain timestamp,no.of records in that file
Thanks in advance
saikumar (3 Replies)
Hi
I'm trying to look through a series of directories in A folder, lets just call it A:
for example:
A/1
A/2
A/3
Etc and I wish to move the files in the folder if they are bigger than a certain size into a structure like below:
A/TooBig/1
A/TooSmall/1
A/TooBig/2
A/TooSmall/2... (1 Reply)
I have one utility in VB which generates attached file(circle.14.mdn_range.properties_VB) & i have created other file(circle.14.mdn_range.properties_UTLFILE) having same contents with UTL_FILE(Oracle running on solaris). But checksum is different for both the files with same contents. Can you... (7 Replies)
Discussion started by: siramitsharma
7 Replies
LEARN ABOUT OSX
sum
CKSUM(1) BSD General Commands Manual CKSUM(1)NAME
cksum, sum -- display file checksums and block counts
SYNOPSIS
cksum [-o 1 | 2 | 3] [file ...]
sum [file ...]
DESCRIPTION
The cksum utility writes to the standard output three whitespace separated fields for each input file. These fields are a checksum CRC, the
total number of octets in the file and the file name. If no file name is specified, the standard input is used and no file name is written.
The sum utility is identical to the cksum utility, except that it defaults to using historic algorithm 1, as described below. It is provided
for compatibility only.
The options are as follows:
-o Use historic algorithms instead of the (superior) default one.
Algorithm 1 is the algorithm used by historic BSD systems as the sum(1) algorithm and by historic AT&T System V UNIX systems as the
sum(1) algorithm when using the -r option. This is a 16-bit checksum, with a right rotation before each addition; overflow is dis-
carded.
Algorithm 2 is the algorithm used by historic AT&T System V UNIX systems as the default sum(1) algorithm. This is a 32-bit checksum,
and is defined as follows:
s = sum of all bytes;
r = s % 2^16 + (s % 2^32) / 2^16;
cksum = (r % 2^16) + r / 2^16;
Algorithm 3 is what is commonly called the '32bit CRC' algorithm. This is a 32-bit checksum.
Both algorithm 1 and 2 write to the standard output the same fields as the default algorithm except that the size of the file in
bytes is replaced with the size of the file in blocks. For historic reasons, the block size is 1024 for algorithm 1 and 512 for
algorithm 2. Partial blocks are rounded up.
The default CRC used is based on the polynomial used for CRC error checking in the networking standard ISO/IEC 8802-3:1989. The CRC checksum
encoding is defined by the generating polynomial:
G(x) = x^32 + x^26 + x^23 + x^22 + x^16 + x^12 +
x^11 + x^10 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1
Mathematically, the CRC value corresponding to a given file is defined by the following procedure:
The n bits to be evaluated are considered to be the coefficients of a mod 2 polynomial M(x) of degree n-1. These n bits are the bits
from the file, with the most significant bit being the most significant bit of the first octet of the file and the last bit being the
least significant bit of the last octet, padded with zero bits (if necessary) to achieve an integral number of octets, followed by one
or more octets representing the length of the file as a binary value, least significant octet first. The smallest number of octets
capable of representing this integer are used.
M(x) is multiplied by x^32 (i.e., shifted left 32 bits) and divided by G(x) using mod 2 division, producing a remainder R(x) of degree
<= 31.
The coefficients of R(x) are considered to be a 32-bit sequence.
The bit sequence is complemented and the result is the CRC.
EXIT STATUS
The cksum and sum utilities exit 0 on success, and >0 if an error occurs.
SEE ALSO md5(1)
The default calculation is identical to that given in pseudo-code in the following ACM article.
Dilip V. Sarwate, "Computation of Cyclic Redundancy Checks Via Table Lookup", Communications of the ACM, August 1988.
STANDARDS
The cksum utility is expected to conform to IEEE Std 1003.2-1992 (``POSIX.2'').
HISTORY
The cksum utility appeared in 4.4BSD.
BSD April 28, 1995 BSD