Hi I have a problem trying to run a while statement.
I have files under one directory that i need to compare to a value in filex and update that file with the result
files in the directory are
DFC1.
DFC5.
DFC345.
DFC344.
DFC9.
The program i am trying to run will take the number... (3 Replies)
Hi,
I need to compare todays file to yesterdays file to find deletes.
I cannot use comm -23 file.old file.new.
Because each record may have a small change in it but is not really a delete.
I have two delimited files. the first field in each file is static. All other fields may change. I... (2 Replies)
Hi,
I hav two files a1.txt and a2.txt,
a1.txt contains:
---------------
asdev ebcdev ....
a2.txt contains:
---------------
asdev ebcdev prod ....
a1.txt will be updated by a process,..
now i want to compare two files and i want to see data which is not in a1.txt
am i clear....??
... (3 Replies)
I need to compare 2 diff type of files and find out the duplicate after comparing each types of files:
Type 1 file name is like: file1.abc
(the extension abc could any 3 characters but I can narrow it down or hardcode for 10/15 combinations).
The other file is file1.bcd01abc (the extension... (2 Replies)
hi i have two files and i want to compare both the files and find out mismatch in 3rd file
file1
00354|1|0|1|1|0|0|0|1|2
52424|1|0|1|1|0|0|0|1|2
43236|1|0|1|1|0|0|0|1|2
41404|1|0|1|1|0|0|0|1|2
79968|1|0|1|1|0|0|0|1|2
file2
00354|1|0|1|1|0|0|0|1|2
52424|1|0|1|1|0|0|0|0|2... (9 Replies)
example data
5666700842511TAfmoham03151008075205999900000001000001000++
5666700843130MAfmoham03151008142606056667008390315100005001
6666666663130MAfmoham03151008142606056667008390315100005001
I'd like to sort on position 10-14 where the characters are eq "130MA".
Then based on positions... (0 Replies)
I have a directory where lot of "gzip" files are dropped in every 5 minutes. There is an application which will process these gzip and move it to another directory but will leave a gzip.out file with lot of output data.
I need to remove all the outfiles except for the one which is being... (1 Reply)
Hi all ,
am using unix aix ..
how to check the duplicates files contents and moving to someother folders
ex ..
i have files called qqq
cat qqq
1
2
3
i have another file qqq02
cat qqq02
1
2
3
here qqq02 has having same contents as qqq file..
i need to check the duplicates files... (1 Reply)
Hey guys,
need help with a script I'm trying to write.
Basically I need to compare the contents of a folder called "profiles"
with a list of files called "template".
when the file matches the contents of the folder it needs to set a variable called "checked" to "1"
Cookies to anyone... (4 Replies)
Greetings. I know enough Unix to be dangerous (!) and know that there is a clever way to do the following and it will save me about a day of agony (this time) and I will use it forever after! (many days of agony saved in the future)!
Basically
I need to find any image files (JPGs, PSDs etc)... (5 Replies)
Discussion started by: Clyde Lovett
5 Replies
LEARN ABOUT OPENDARWIN
cksum
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.
DIAGNOSTICS
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