Programmers have been known to call it ‘hook’.
Edit:
Modern programmers have a lot more hooky things to cope with than just the old QUESTION MARK from antediluvian typewriter keyboards. For example, here are a bunch of characters whose names contain ‘question’, or ‘glottal’, or ‘hook’, or ‘interro’:
Code chr GenCat Script Name
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U+003F ? GC=Po SC=Common QUESTION MARK
U+00BF ¿ GC=Po SC=Common INVERTED QUESTION MARK
U+01BE ƾ GC=Ll SC=Latin LATIN LETTER INVERTED GLOTTAL STOP WITH STROKE
U+0241 Ɂ GC=Lu SC=Latin LATIN CAPITAL LETTER GLOTTAL STOP
U+0242 ɂ GC=Ll SC=Latin LATIN SMALL LETTER GLOTTAL STOP
U+0294 ʔ GC=Lo SC=Latin LATIN LETTER GLOTTAL STOP
U+0296 ʖ GC=Ll SC=Latin LATIN LETTER INVERTED GLOTTAL STOP
U+02A1 ʡ GC=Ll SC=Latin LATIN LETTER GLOTTAL STOP WITH STROKE
U+02A2 ʢ GC=Ll SC=Latin LATIN LETTER REVERSED GLOTTAL STOP WITH STROKE
U+02C0 ˀ GC=Lm SC=Common MODIFIER LETTER GLOTTAL STOP
U+02C1 ˁ GC=Lm SC=Common MODIFIER LETTER REVERSED GLOTTAL STOP
U+02DE ˞ GC=Sk SC=Common MODIFIER LETTER RHOTIC HOOK
U+02E4 ˤ GC=Lm SC=Latin MODIFIER LETTER SMALL REVERSED GLOTTAL STOP
U+0309 ◌̉ GC=Mn SC=Inherited COMBINING HOOK ABOVE
U+0321 ◌̡ GC=Mn SC=Inherited COMBINING PALATALIZED HOOK BELOW
U+0322 ◌̢ GC=Mn SC=Inherited COMBINING RETROFLEX HOOK BELOW
U+061F ؟ GC=Po SC=Common ARABIC QUESTION MARK
U+097D ॽ GC=Lo SC=Devanagari DEVANAGARI LETTER GLOTTAL STOP
U+203D ‽ GC=Po SC=Common INTERROBANG
U+2047 ⁇ GC=Po SC=Common DOUBLE QUESTION MARK
U+2048 ⁈ GC=Po SC=Common QUESTION EXCLAMATION MARK
U+2049 ⁉ GC=Po SC=Common EXCLAMATION QUESTION MARK
U+2E18 ⸘ GC=Po SC=Common INVERTED INTERROBANG
U+2E2E ⸮ GC=Po SC=Common REVERSED QUESTION MARK
U+FE16 ︖ GC=Po SC=Common PRESENTATION FORM FOR VERTICAL QUESTION MARK
U+FE56 ﹖ GC=Po SC=Common SMALL QUESTION MARK
U+FF1F ? GC=Po SC=Common FULLWIDTH QUESTION MARK
Now that characters have official names that are so tediously long, like LATIN LETTER INVERTED GLOTTAL STOP WITH STROKE, it’s even more likely that short slangy forms will get used, although probably only locally.