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GNU Info (gdb.info)C ConstantsC and C++ constants ................... GDB allows you to express the constants of C and C++ in the following ways: * Integer constants are a sequence of digits. Octal constants are specified by a leading `0' (i.e. zero), and hexadecimal constants by a leading `0x' or `0X'. Constants may also end with a letter `l', specifying that the constant should be treated as a `long' value. * Floating point constants are a sequence of digits, followed by a decimal point, followed by a sequence of digits, and optionally followed by an exponent. An exponent is of the form: `e[[+]|-]NNN', where NNN is another sequence of digits. The `+' is optional for positive exponents. A floating-point constant may also end with a letter `f' or `F', specifying that the constant should be treated as being of the `float' (as opposed to the default `double') type; or with a letter `l' or `L', which specifies a `long double' constant. * Enumerated constants consist of enumerated identifiers, or their integral equivalents. * Character constants are a single character surrounded by single quotes (`''), or a number--the ordinal value of the corresponding character (usually its ASCII value). Within quotes, the single character may be represented by a letter or by "escape sequences", which are of the form `\NNN', where NNN is the octal representation of the character's ordinal value; or of the form `\X', where `X' is a predefined special character--for example, `\n' for newline. * String constants are a sequence of character constants surrounded by double quotes (`"'). Any valid character constant (as described above) may appear. Double quotes within the string must be preceded by a backslash, so for instance `"a\"b'c"' is a string of five characters. * Pointer constants are an integral value. You can also write pointers to constants using the C operator `&'. * Array constants are comma-separated lists surrounded by braces `{' and `}'; for example, `{1,2,3}' is a three-element array of integers, `{{1,2}, {3,4}, {5,6}}' is a three-by-two array, and `{&"hi", &"there", &"fred"}' is a three-element array of pointers. automatically generated by info2www version 1.2.2.9 |