say i have these many file in a directory named exam.
1)/exam/newfolder/link.txt.
2)/exam/newfolder1/
and i create a tar say exam.tar
well the problem is,
when i read the tar file i dont find any metadata about the directories,as you cannot create a tar containig empty directories.
on the... (2 Replies)
awk experts,
I have a big file of 4000 columns with header. Would like to print the columns with string value of "Commands" in header. File has "," separator. This file is on ESX host with Bash.
Thanks,
Arv (21 Replies)
Friends,
I need help with the following in UNIX.
Merge all csv files in one folder considering only 1 header row and ignoring header of all other files.
FYI - All files are in same format and contains same headers.
Thank you (4 Replies)
Hi All,
I have got a requirement.
I have a source file, EMPFULL.txt and I need to split the data for every 30 records
and place a Typical Header as below with system and page number too.
2012.01.03 Employee Dept Report 1... (6 Replies)
Hi,
I have an input like this
1 2 3 4
2 3 4 5
4 5 6 7
I would like to count the no. of columns and print a header with a prefix "Col".
I would also like to count the no. of rows and print as first column with each line number with a prefix "Row"
So, my output would be
... (2 Replies)
Hello There...
I have a sample input file ..
number:department:amount
125:Market:125.23
126:Hardware store:434.95
127:Video store:7.45
128:Book store:14.32
129:Gasolline:16.10
I will be doing some manipulations on all the records except the header, but the header should always be... (2 Replies)
I have this code below that only prints out certain columns from the first two rows (doesn't affect rows 3 and beyond). How can I do the same on a partial header pattern “G_TP” instead of having to know specific column numbers (e.g. 374-479)? I've tried many other commands within this pipe with no... (4 Replies)
I've been struggling with this one for quite a while and cannot seem to find a solution for this find/replace scenario. Perhaps I'm getting rusty.
I have a file that contains a number of metrics (exactly 3 fields per line) from a few appliances that are collected in parallel. To identify the... (3 Replies)
Discussion started by: verdepollo
3 Replies
LEARN ABOUT PHP
crc32
CRC32(3) 1 CRC32(3)crc32 - Calculates the crc32 polynomial of a stringSYNOPSIS
int crc32 (string $str)
DESCRIPTION
Generates the cyclic redundancy checksum polynomial of 32-bit lengths of the $str. This is usually used to validate the integrity of data
being transmitted.
Warning
Because PHP's integer type is signed many crc32 checksums will result in negative integers on 32bit platforms. On 64bit installa-
tions all crc32(3) results will be positive integers though.
So you need to use the "%u" formatter of sprintf(3) or printf(3) to get the string representation of the unsigned crc32(3) checksum
in decimal format.
For a hexadecimal representation of the checksum you can either use the "%x" formatter of sprintf(3) or printf(3) or the dechex(3)
conversion functions, both of these also take care of converting the crc32(3) result to an unsigned integer.
Having 64bit installations also return negative integers for higher result values was considered but would break the hexadecimal
conversion as negatives would get an extra 0xFFFFFFFF######## offset then. As hexadecimal representation seems to be the most common
use case we decided to not break this even if it breaks direct decimal comparisons in about 50% of the cases when moving from 32 to
64bits.
In retrospect having the function return an integer maybe wasn't the best idea and returning a hex string representation right away
(as e.g. md5(3) does) might have been a better plan to begin with.
For a more portable solution you may also consider the generic hash(3). hash("crc32b", $str) will return the same string as
dechex(crc32($str)).
PARAMETERS
o $str
- The data.
RETURN VALUES
Returns the crc32 checksum of $str as an integer.
EXAMPLES
Example #1
Displaying a crc32 checksum
This example shows how to print a converted checksum with the printf(3) function:
<?php
$checksum = crc32("The quick brown fox jumped over the lazy dog.");
printf("%u
", $checksum);
?>
SEE ALSO hash(3), md5(3), sha1(3).
PHP Documentation Group CRC32(3)