How to Recover panic in Golang
Defer, Panic, and Recover in Go.
panic
During a typical panic, normal execution stops, all deferred function calls in that goroutine are executed, and the program crashes with a log message.
package main
func main() {
panic("invalid")
}
...
How to Use Deferred Function Calls in Golang
Understanding defer in Go.
Deferred Function Calls
A defer statement is an ordinary function or method call prefixed by the keyword defer. The function and argument expressions are evaluated when the statement is executed, but the actual call is def...
How to Add Two Numbers in Go
An example program using numbers.
Integers And Floating Point Numbers
Go has several different types to represent numbers. Generally we split numbers into two different kinds: integers and floating-point numbers.
Make a main.go file containing the ...
How to Change the Current Directory in Go
In Golang, there are 2 ways to change the current directory.
Using Dir Property
Usually if you need a command to run from a specific directory, you can specify that as the Dir property on the Command, for example:
package main
import (
"os/...
How to Get the System Hostname in Python
In Python, there are 3 ways to get the system hostname.
Using gethostname Method
The socket.gethostname() method returns a string containing the hostname of the machine where the Python interpreter is currently executing. For example,
#!/usr/bin...
How to Convert Float to Integer in Rust
In Rust, there are 2 ways to convert float to integer.
Using as Keyword
Executing an as expression casts the value on the left-hand side to the type on the right-hand side.
An example of an as expression:
fn main() {
let a = 3.6415_f64;
l...
How to Pipe Several Commands in Go
In Golang, there are 2 ways to pipe several commands.
Using piped commands
For example, this function retrieves the CPU model name using piped commands:
package main
import (
"fmt"
"os/exec"
)
func main() {
cmd := "cat /proc/cpuinfo | eg...
How to Execute a Shell Command in Go
In Golang, using the exec.Command() function is the easiest way to execute a shell command
Using exec.Command Function
Command returns the Cmd struct to execute the named program with the given arguments.
You can execute a shell command using the e...
How to Generate a UUID in Go
In Golang, there are 4 ways to generate a uuid.
Using uuid Package
install
Use the following command to download the repository to the local file system.
install
go mod tidy
go get github.com/google/uuid
go install github.com...
How to List all Standard Packages in Go
In Golang, there are 2 ways to list all standard packages.
Using packages
go install
Use the following command to download the repository to the local file system.
install
go get golang.org/x/tools/go/packages
go install golang.or...
How to Access Command Line Parameters in Rust
In Rust, there are 2 ways to access command line parameters.
Using std::env::args Function
This function actually returns the arguments that this program was started with. See the following example:
use std::env;
fn main() {
for arg in env::...
How to Get the Directory of the Currently Running File in Go
In Golang, there are 3 ways to get the directory of the currently running file.Using os.Executable Function
Executable returns the path name for the executable that started the current process.
The easiest way to get the directory of the currently ...
How to Execute a Program or Call a System Command in Python
In Python, there are 3 ways to execute a program or call a system command.
Using subprocess Module
The subprocess module allows you to spawn new processes, connect to their input/output/error pipes, and obtain their return codes. See the following e...
How to Make a Time Delay in Python
In Python, there are 2 ways to make a time delay.
Using time.sleep Function
This function actually suspends execution of the calling thread for the given number of seconds. The argument may be a floating point number to indicate a more precise sleep...
How to Check whether a File Exists in Python
In Python, there are 3 ways to check if a file exists.
Using os.path.exists Method
Return True if path refers to an existing path or an open file descriptor. Returns False for broken symbolic links. On some platforms, this function may return False ...