& sign will not copy to clipboard-CodePudding

I am trying to copy the & sign to the clipboard using the code below. But it just gives me an error "| was unexpected at this time."

import os

def addToClipBoard(text):
    command = 'echo '   text.strip()   '| clip'
    os.system(command)

addToClipBoard('&')

Is there a way to make it work with a little tweaking, or do I have to use another way?

CodePudding user response：

you running shell command to copy text to clip board but '&' sign in shell command is used to run command in background so maybe that's why it's not working.

you can directly copy text to clip board using python like this :

import pyperclip
pyperclip.copy('The text to be copied to the clipboard.')

code from here : Python script to copy text to clipboard

CodePudding user response：

You need to quote (or escape) the & character:

import os

def addToClipBoard(text):
    command = "echo '{}' | clip".format(text.strip())
    os.system(command)

addToClipBoard('&')

In Bash, & is a control operator. It’s a shell builtin, meaning, it’s literally a core part of the Bash tool set. (Copied from BashItOut - Ampersands & on the command line)

EDIT

As @CharlesDuffy mentioned in the comments, there's a better way of doing this for security reasons.

Consider the string $(rm -rf ~/*)'$(rm -rf ~/*)' -- trying to copy it to the clipboard is going to result in a deleted home directory even with the extra quotes, because the quotes inside the string itself cancel them out.

The solution is to use shlex.quote() as a safer means of adding literal quotes.

import os
import shlex

def addToClipBoard(text):
    command = "printf '%s\n' {} | clip".format(shlex.quote(text))
    os.system(command)

addToClipBoard('&')

NOTE: This last section is based on the comments by @CharlesDuffy.

CodePudding user response：

os.system doesn't itself know that the | character is supposed to redirect stdin, and depending on the OS it's not necessarily running your command through a shell that would do that. If you use subprocess instead you can pass data to stdin directly, e.g.:

import subprocess

def add_to_clipboard(text: str) -> None:
    subprocess.run("clip", text=True, input=text.strip())