a complete c program has to have a function with name 'main'. this is the function called...

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1.21. A complete C program has to have a function with name 'main'. This is the

function called by the operating system. It must return an int value indicating whether the prograam executed correctly or if there was an error. In UNIX, the main program returns0 to indicate no errors. Their are several valid forms:

22. int main()23. int main(argc, argv)24. int main(argc, argv, envp) The parameters are set up by the operating system

when the program starts. The traditional arg stands for argument.

Pointers25. pointer::=#( "*" | #type_qualifier),

26. declarator::=pointer | direct_declarator,

Functions and Arrays

27. post_declarator::="["constant_expression"]" | "("parameter_list")" |"("identifier_list")"

28. direct_declarator::=identifier | "("declarator")" | direct_declarator post_declarator,

29. abstract_declarator::=pointer | pointer direct_abstract_declarator,

30. direct_abstract_declarator::= "(" abstract_declarator ")" |O( direct_abstract_declarator) O("[" O(constant_expression) "]" | "(" O(parameter_list)")" ),

. . . . . . . . . ( end of section Declarations) <<Contents | End>>Statements

1. statement::=labeled_statement | compound_statement | expression_statement |selection_statement | iteration_statement | jump_statement

Branch2. jump_statement::="goto" identifier";" | "continue" ";" | "break;" | "return"

expression ";",Structured

3. loop::=iteration_statement.4. iteration_statement::="while" "("expression")" statement | "do" statement

"while" "("expression")" ";" | for_statement.

5. for_statement::="for" "("expression ";" expression ";" expression")"statement,

6. selection_statement::=if_statement | "switch" "("expression")" statement,7. if_statement::="if ("expression")" statement | "if" "("expression")" statement

"else" statement.

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8. expression_statement::= expression ";",

9. labeled_statement::=identifier ":" statement | "case" constant_expression ":"statement | "default" ":" statement,

Compound10. compound_statement::=block | "{" #statement "}",

11. block::="{" declaration #declaration #statement "}",

. . . . . . . . . ( end of section Statements) <<Contents | End>>Pre-Processor Commands

1. preprocess_token::=identifier | constant | string_literal | operator | punctuator |each Non-white space not one of the previous,

2. header_char::=any character except new_line | and | >,3. header_name::=#(header_char),

4. new_line::=new_line character,

5. Left_paren::=left parenthesis with no white space before it,

6. control_line::="#include" (#(preprocess_token | header_name) new_line |"#define" identifier #(preprocess_token) new_line | "#define" identifier left_parenidentifier_list #(preprocess_token) new_line, | "#undef" identifier new_line | "#line"

preprocess_token new_line | "#error" preprocess_token new_line | "#pragma" preprocess_token new_line | "#"new_line,

7. endif_line::="#endif" new_line,

8. elif_group::="#elif" constant_expression new_line pp_group,

9. else_group::="#else" new_line pp_group,

10. if_group::=("#if" constant_expression | "#ifdef" identifier | "#ifndef"identifier) new_line pp_group,

11. if_part::=if_group #(elif_group) else_group endif_line,

12. pp_part::=#preprocess_token new_line | if_part | control_line,

13. pp_group::=#(pp_part),

. . . . . . . . . ( end of section Pre-Processor Commands) <<Contents | End>>

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. . . . . . . . . ( end of section Syntax of The C Programming Language) <<Contents |End>>

Endyntax of The C Programming Language

Cross-Refferences1. ASCII::= See http://www.csci.csusb.edu/dick/samples/comp.text.ASCII.html

Used_in The definition of C++ [ c++.syntax.html ]

Used_in The definition of Java [ java.syntax.html ]NotationThis uses my XBNF Extended BNF Notation where "|" indicates "or", "(...)" indicates

priority. For more information see [ intro_ebnf.html ]

The following abbreviations are also used:1. O(_)::= 0 or 1 occurrences,2. N(_)::= 1 or more occurrence3. L(_)::= a comma separated list4. #(_)::= 0 or more occurrences.

5. S(E,Op)::=serial_operator_expression(E, Op)6. serial_operator_expression(E,Op)::= E #(Op E).

S(E,Op) = E Op E Op E Op ... E

It also uses the following shorthand

Lexemes1. identifier::=nondigit #(nondigit | digit),

2. nondigit::="_" | "a" | "A" | "b" | "B" | "c" | "C" | "d" | "D" | "e" | "E" | "f" | "F" | "g"| "G" | "h" | "H" | "i" | "I" | "j" | "J" | "k" | "K" | "l" | "L" | "m" | "M" | "n" | "N" | "o" | "O" |"p" | "P" | "q" | "Q" | "r" | "R" | "s" | "S" | "t" | "T" | "u" | "U" | "v" | "V" | "w" | "W" | "x" |"X" | "y" | "Y" | "z" | "Z",

3. digit::="0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9",

4. punctuator::="[" | "]" | "(" | ")" | "{" | "}" | "*" | "," | ":" | "=" | ";" | "..." | "#",

5. operator::="[" | "]" | "(" | ")" | "." | "->" | "++" | "--" | "&" | "*" | "+" | "-" | "~" | "!"| "sizeof" | "/" | "%" | "<<" | ">>" | "<" | ">" | "<=" | ">=" | "==" | "!=" | "^" | "|" | "&&" |"||" | "?" | ":" | "=" | "*=" | "/=" | "%=" | "+=" | "-=" | "<<=" | ">>=" | "&=" | "^=" | "||=" |"," | "#" | "##",

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6. infix::= "->" | "&" | "*" | "+" | "-" | "/" | "%" | "<<" | ">>" | "<" | ">" | "<=" | ">=" |"==" | "!=" | "^" | "|" | "&&" | "||" | "=" | "*=" | "/=" | "%=" | "+=" | "-=" | "<<=" | ">>=" |"&=" | "^=" | "||=" | "," ,

7. prefix::= "++" | "--" | "&" | "*" | "+" | "-" | "~" | "!" | "sizeof" ,

8. postfix::= "++" | "--",

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Robertadhiabram

parman9. integer_suffix::=#(unsigned_suffix) | #(long_suffix),

10. unsigned_suffix::="u" | "U",

11. long_suffix::="l" | "L",

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12. sign::="+" | "-",

13. octal_constant::="0" #(octal_digit),

14. octal_digit::="0" | "1" | "2" | "3" | "4" | "5" | "6" | "7",

15. hex_constant::=("0x" | "0X") (hex_digit),

16. hex_digit::="0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" | "a" | "b" | "c" | "d"| "e" | "f" | "A" | "B" | "C" | "D" | "E" | "F",

17. decimal_constant::=non_zero_digit #(digit),

18. non_zero_digit::="1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9",

19. integer_constant::=(decimal_constant | octal_constant | hex_constant) |

integer_suffix,20. float_suffix::="f" | "l" | "F" | "L",

21. fraction::=#digit "." digit #digit,

22. exponent_part::=("e" | "E") sign #(digit),

23. float_constant::=fraction (exponent_part|) (float_suffix|)|(decimal_constant(exponent_part|) float_suffix,

24. enumeration_constant::=identifier,

25. char_constant::=char~(double_quote|eoln|backslash)| escape_sequence,

26. escape_sequence::=backslash (char | "0" #octal_digit |"0x"#hexadecimal_digit),

27. character_constant::="'" char_constant"'" ,

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constant :=::=float_constant | integer_constant | enumeration_constant |character_constant,

28. string__char::=char~(double_quote|eoln|backslash)| escape_sequence,

29. string_literal::=double_quote #(string_char) double_quote,

. . . . . . . . . ( end of section Lexemes) <<Contents | End>>Expressions

Expressions are made up by applying operators to primary_expressions.1. primary_expression::= variable | constant | string_literal | "(" expression ")",

2. variable::= identifier & declared and in scope of declaration.3. argument_list::=List(assignment_expression),

OperatorsSymbol See"("... ")" primary_expression cast_expression function_call"." part of a structure"-" additive_expression unary_expression"->" part of a pointed at structure

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"--" unary_expression postfix_expression

"-=" assignment_expression"&" AND_expression bitwise Boolean"&=" assignment_expression"&" address_of unary_expression

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"&&" logical_AND_expression"*" multiplicative_expression contents of pointer unary_expression"*=" assignment_expression"+" additive_expression unary_expression"++" unary_expression postfix_expression

"+=" assignment_expression"~" bitwise negation prefix

Robertadhi

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abram parman

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"!" logical negation prefix

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"!=" equality_expression

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"sizeof" unary_expression

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"/" multiplicative_expression divide

"/=" assignment_expression"%" multiplicative_expression mod"%=" assignment_expression"<" relational_expression

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"<<" shift_expression left

Robertadhiabram

parman"<<=" assignment_expression"<=" relational_expression">" relational_expression">>" shift_expression right

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">=" relational_expression">>=" assignment_expression"==" equality_expression"=" assignment_expression" "̂ XOR_expression exclusive-or bitwise

"^=" assignment_expression"|" OR_expression bitwise or "||" logical_OR_expression"||=" assignment_expression..."?"... ":"... conditional_expression"," expression (discard previous value)

Arithmetic4. post_fix::="++" | "--",

5. post_fix_expression::=(primary_expression) #(post_fix),

6. unary_operator::="&" | "*" | "+" | "-" | "!" | "-",

7. pre_fix::="++" | "--" | "sizeof",

8. unary_expression::=#(pre-fix) post_fix_expression | unary_operator cast_expression | "sizeof" "(" type_name")",

9. cast_expression::=#(type_name) unary_expression. This implies that casts aredone after doing post-fix operations..

10. multiplicative_expression::=S(cast_expression, multiplicative_operator).[ serial_operator_expression ]

The rule above means that 'casts' are done before multiplication and division, andthat multiplication and division are done from left to right.

11. multiplicative_operator::="*" | "%" | "/",

12. additive_expression::=S(multiplicative_expression, additive_operator). Thismeans that addition and subtraction occurs after multiplication and from left to right.

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13. additive_operator::="+" | "-",

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Shifts