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How to convert an IPv4 address into a integer in C#?
...ses. Meanwhile, the IPAddress.Address property, while deprecated, is an Int64 that returns the unsigned 32-bit value of the IPv4 address (the catch is, it's in network byte order, so you need to swap it around).
For example, my local google.com is at 64.233.187.99. That's equivalent to:
64*2^24 + ...
Maximum length for MySQL type text
... (255 Bytes)
BLOB, TEXT L + 2 bytes, where L < 2^16 (64 Kilobytes)
MEDIUMBLOB, MEDIUMTEXT L + 3 bytes, where L < 2^24 (16 Megabytes)
LONGBLOB, LONGTEXT L + 4 bytes, where L < 2^32 (4 Gigabytes)
L is the number of bytes in your text field. So the maximum numb...
What is causing “Unable to allocate memory for pool” in PHP?
...allowing only 32MB is ridiculously low. PHP was designed when servers were 64MB and most scripts were using one php file per page. Nowadays solutions like Magento require more than 10k files (~60Mb in APC). You should allow enough memory so most of php files are always cached. It's not a waste, it's...
float64 with pandas to_csv
...tp://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789...
What is the difference between Digest and Basic Authentication?
...d the requested URI.
Whereas Basic Authentication uses non-encrypted base64 encoding.
Therefore, Basic Authentication should generally only be used where transport layer security is provided such as https.
See RFC-2617 for all the gory details.
...
Shell script to send email [duplicate]
...xtensions
SUB_CHARSET=$(echo ${SUBJECT} | file -bi - | cut -d"=" -f2)
SUB_B64=$(echo ${SUBJECT} | uuencode --base64 - | tail -n+2 | head -n+1)
NB_FILES=$(echo ${FILES} | wc -w)
NB=0
cat <<EOF | /usr/sbin/sendmail -t
From: ${FROM}
To: ${TO}
MIME-Version: 1.0
Content-Type: multipart/mixed; boun...
Hexadecimal To Decimal in Shell Script
...nteger overflow error, e.g. echo $((077E9F2DBF49D100001#FF)) overflows the 64-bit integer limit of 2^64. bc handles this properly.
– roblogic
May 2 '18 at 1:04
...
Fast way of counting non-zero bits in positive integer
...
I tried adapting Óscar's and Adam's solutions to process the integer in 64-bit and 32-bit chunks, respectively. Both were at least ten times slower than bin(n).count("1") (the 32-bit version took about half again as much time).
On the other hand, gmpy popcount() took about 1/20th of the time of ...
How to update Python?
...ow, these answers are for the same bit-versions, and by bit-version I mean 64-bit vs. 32-bit. For example, these answers would apply to updating from 64-bit Python-2.7.10 to 64-bit Python-2.7.11, ie: the same bit-version. While it is possible to install two different bit versions of Python together,...
Reference — What does this symbol mean in PHP?
... |
-------------------------------------------
|Place Value | 128| 64| 32| 16| 8| 4| 2| 1|
-------------------------------------------
This representation of 1 Byte
1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 = 255 (1 Byte)
A few examples for better understanding
The "AND" operator: &
...