Info Catalog gdb: C Operators gdb: C gdb: C Plus Plus Expressions

gdb: C Constants

 
 15.4.1.2 C 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.
 
      Wide character constants can be written by prefixing a character
      constant with 'L', as in C. For example, 'L'x'' is the wide form of
      'x'.  The target wide character set is used when computing the
      value of this constant (Character Sets).
 
    * 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.
 
      Wide string constants can be written by prefixing a string constant
      with 'L', as in C. The target wide character set is used when
      computing the value of this constant (Character Sets).
 
    * 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.
 

Info Catalog gdb: C Operators gdb: C gdb: C Plus Plus Expressions