How do I pass ">>" or "<<" to my script without the terminal trying to interpret it as me either appending to something or getting stdin?

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My python script can take a series of bitwise operators as one of its arguments. They all work fine except for "=<<" which is roll left, and "=>>" which is roll right. I run my script like ./script.py -b +4,-4,=>>10,=<<1, where anything after -b can be any combination of similar operations. As soon as the terminal sees "<<" though, it just drops the cursor to a new line after the command and asks for more input instead of running the script. When it sees ">>", my script doesn't process the arguments correctly. I know it's because bash uses these characters for a specific purpose, but I'd like to get around it while still using "=>>" and "=<<" in my arguments for my script. Is there any way to do it without enclosing the argument in quotation marks?

Thank you for your help.

linux bash
1 Answers

You should enclose the parameters that contain special symbols into single quotation marks (here, echo represents your script):

> echo '+4,-4,=>>10,=<<1'
+4,-4,=>>10,=<<1

Alternatively, save the parameters to a file (say, params.txt) and read them from the file onto the command line using the backticks:

> echo `cat params.txt`
+4,-4,=>>10,=<<1

Lastly, you can escape some offending symbols:

> echo +4,-4,=\>\>10,=\<\<1
+4,-4,=>>10,=<<1
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