Boolean Expressions

False values

false
0 (zero)
0.0 (zero)
NULL
End-of-string character (char: 0) ('\x00')
  • A false logical expression resolves to a numeric value of 0.

True values

true
1 (any non-zero integer or floating point value)
"..." (any empty or non-empty string)
EOF (end-of-file) (unsigned char: 255; signed char: -1)
  • A true logical expression resolves to a numeric value of 1.