Shortest way to get an EOF Error

APL (Dyalog Unicode) 17.0, 0 bytes

Dyalog 17.0 expects programs to terminate themselves cleanly and will throw an EOF INTERRUPT (and exit with a code 2) if they don't: Try it online!

In contrast, here is the minimal program which does terminate itself cleanly, causing no error (and code 0 upon exit): Try it online!

Python 3, 1 byte

(

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A plain opening bracket is interpreted as the start of a tuple. Just having one bracket is enough to raise an EOF error. Also works with [ and {.

Keg, 1 byte

?

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When there's no input, an EOF is raised:

Traceback (most recent call last):
 File "/opt/keg/Keg.py", line 500, in <module>
   exec(header + code + footer)
 File "<string>", line 6, in <module>
 File "/opt/keg/KegLib.py", line 119, in Input
   item = input()
 EOFError: EOF when reading a line

Also works with ¿