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How do I set a variable to the output of a command in Bash?
...equired, just for readability.
About sudo cmd | grep ... | cut ...
shell=$(cat /etc/passwd | grep $USER | cut -d : -f 7)
echo $shell
/bin/bash
(Please avoid useless cat! So this is just one fork less:
shell=$(grep $USER </etc/passwd | cut -d : -f 7)
All pipes (|) implies forks. Where another pr...
Go > operators
...y Arithmetic operators and its the same in other languages here is a basic PHP , C , Go Example
GO
package main
import (
"fmt"
)
func main() {
var t , i uint
t , i = 1 , 1
for i = 1 ; i < 10 ; i++ {
fmt.Printf("%d << %d = %d \n", t , i , t<<i)
}
...
Str_replace for multiple items
...s:
str_replace(array(':', '\\', '/', '*'), ' ', $string);
Or, in modern PHP (anything from 5.4 onwards), the slighty less wordy:
str_replace([':', '\\', '/', '*'], ' ', $string);
share
|
improv...
How does this giant regex work?
...ently found the code below in one of my directories, in a file called doc.php . The file functions or links to a file manager. It's quite nicely done. Basically, it lists all the files in the current directory, and it lets you change directories.
...
How can I remove duplicate rows?
...erver LEFT JOIN is less efficient than NOT EXISTS sqlinthewild.co.za/index.php/2010/03/23/… The same site also compares NOT IN vs NOT EXISTS. sqlinthewild.co.za/index.php/2010/02/18/not-exists-vs-not-in Out of the 3 I think NOT EXISTS performs best. All three will generate a plan with a self join ...
Why does my JavaScript code receive a “No 'Access-Control-Allow-Origin' header is present on the req
...risks before using this code.
It's very simple to solve if you are using PHP. Just add the following script in the beginning of your PHP page which handles the request:
<?php header('Access-Control-Allow-Origin: *'); ?>
If you are using Node-red you have to allow CORS in the node-red/sett...
MySQL foreign key constraints, cascade delete
...
If your cascading deletes nuke a product because it was a member of a category that was killed, then you've set up your foreign keys improperly. Given your example tables, you should have the following table setup:
CREATE TABLE categories (
id int unsigned not null primary key,
name VA...
string sanitizer for filename
I'm looking for a php function that will sanitize a string and make it ready to use for a filename. Anyone know of a handy one?
...
各编程语言读写文件汇总 - C/C++ - 清泛网 - 专注C/C++及内核技术
...件尾后，即文件原先的内容会被保留。
导航：
一、PHP
二、C#
三、C
3.1、fgets、fputs文本读写
3.2、fread、fwrite二进制读写
四、C++
五、Java
PHP读写文件：
// 写文件
$fp = fopen("log.txt", "a");
fwrite($fp, $str);
fclose(...
What is SQL injection? [duplicate]
...ta or even changing data that they shouldn't be allowed to do.
Example in PHP:
$password = $_POST['password'];
$id = $_POST['id'];
$sql = "UPDATE Accounts SET PASSWORD = '$password' WHERE account_id = $id";
Now suppose the attacker sets the POST request parameters to "password=xyzzy" and "id=acc...