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Why should casting be avoided? [closed]
... compiler won't warn you about those potential problems. Just for example, char a=(char)123456;. The exact result of this implementation defined (depends on the size and signedness of char), and except in rather strange situations, probably isn't useful. C casts also vary in whether they're somethin...
How do you get the list of targets in a makefile?
...al with false positives from other output sections.
if ($$1 !~ "^[#.]")
Selectively ignores blocks:
# ... ignores non-targets, whose blocks start with # Not a target:
. ... ignores special targets
All other blocks should each start with a line containing only the name of an explicitly defined...
What's the complete range for Chinese characters in Unicode?
...gh the CJK Unicode FAQ (which does include "Chinese, Japanese, and Korean" characters)
The "East Asian Script" document does mention:
Blocks Containing Han Ideographs
Han ideographic characters are found in five main blocks of the Unicode Standard, as
shown in Table 12-2
Table 12-2. Blocks Contain...
What method in the String class returns only the first N characters?
...input string to is longer than the provided length N , only the first N characters are to be displayed.
12 Answers
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How does UTF-8 “variable-width encoding” work?
... Like this:
0xxx xxxx A single-byte US-ASCII code (from the first 127 characters)
The multi-byte code-points each start with a few bits that essentially say "hey, you need to also read the next byte (or two, or three) to figure out what I am." They are:
110x xxxx One more byte follows
11...
hexadecimal string to byte array in python
...t bytes.fromhex throws an error when the input string has an odd number of characters: bytes.fromhex("aab") → ValueError: non-hexadecimal number found in fromhex() arg at position 3.
– Константин Ван
Jul 24 '18 at 17:35
...
PHP best way to MD5 multi-dimensional array?
...) function.
Test results for multi-dimensional array with md5-hashes (32 char) in keys and values:
Test name Repeats Result Performance
serialize 10000 0.761195 sec +0.00%
print_r 10000 1.669689 sec -119.35%
json_encode 10000...
How to extract the first two characters of a string in shell scripting?
...{long:0:2}" ; echo "${short}"
US
This will set short to be the first two characters of long. If long is shorter than two characters, short will be identical to it.
This in-shell method is usually better if you're going to be doing it a lot (like 50,000 times per report as you mention) since there...
IOCTL Linux device driver [closed]
...vr_version_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%s\n", DRIVER_RELEASE);
}
static DEVICE_ATTR(version, S_IRUGO, mydrvr_version_show, NULL);
And during driver setup:
device_create_file(dev, &dev_attr_version);
You would then ha...
getMinutes() 0-9 - How to display two digit numbers?
...rent_date.getMinutes()).slice(-2);
The technique is take the rightmost 2 characters (slice(-2)) of "0" prepended onto the string value of getMinutes(). So:
"0"+"12" -> "012".slice(-2) -> "12"
and
"0"+"1" -> "01".slice(-2) -> "01"
...