The GNU Fortran Compiler: ISO_C

10.2 `ISO_C_BINDING`

Standard:: Fortran 2003 and later, GNU extensions

The following intrinsic procedures are provided by the module; their definition can be found in the section Intrinsic Procedures of this manual.

C_ASSOCIATED
C_F_POINTER
C_F_PROCPOINTER
C_FUNLOC
C_LOC
C_SIZEOF

The ISO_C_BINDING module provides the following named constants of type default integer, which can be used as KIND type parameters.

In addition to the integer named constants required by the Fortran 2003 standard and C_PTRDIFF_T of TS 29113, GNU Fortran provides as an extension named constants for the 128-bit integer types supported by the C compiler: C_INT128_T, C_INT_LEAST128_T, C_INT_FAST128_T. Furthermore, if __float128 is supported in C, the named constants C_FLOAT128, C_FLOAT128_COMPLEX are defined.

Fortran Type	Named constant	C type	Extension
`INTEGER`	`C_INT`	`int`
`INTEGER`	`C_SHORT`	`short int`
`INTEGER`	`C_LONG`	`long int`
`INTEGER`	`C_LONG_LONG`	`long long int`
`INTEGER`	`C_SIGNED_CHAR`	`signed char`/`unsigned char`
`INTEGER`	`C_SIZE_T`	`size_t`
`INTEGER`	`C_INT8_T`	`int8_t`
`INTEGER`	`C_INT16_T`	`int16_t`
`INTEGER`	`C_INT32_T`	`int32_t`
`INTEGER`	`C_INT64_T`	`int64_t`
`INTEGER`	`C_INT128_T`	`int128_t`	Ext.
`INTEGER`	`C_INT_LEAST8_T`	`int_least8_t`
`INTEGER`	`C_INT_LEAST16_T`	`int_least16_t`
`INTEGER`	`C_INT_LEAST32_T`	`int_least32_t`
`INTEGER`	`C_INT_LEAST64_T`	`int_least64_t`
`INTEGER`	`C_INT_LEAST128_T`	`int_least128_t`	Ext.
`INTEGER`	`C_INT_FAST8_T`	`int_fast8_t`
`INTEGER`	`C_INT_FAST16_T`	`int_fast16_t`
`INTEGER`	`C_INT_FAST32_T`	`int_fast32_t`
`INTEGER`	`C_INT_FAST64_T`	`int_fast64_t`
`INTEGER`	`C_INT_FAST128_T`	`int_fast128_t`	Ext.
`INTEGER`	`C_INTMAX_T`	`intmax_t`
`INTEGER`	`C_INTPTR_T`	`intptr_t`
`INTEGER`	`C_PTRDIFF_T`	`ptrdiff_t`	TS 29113
`REAL`	`C_FLOAT`	`float`
`REAL`	`C_DOUBLE`	`double`
`REAL`	`C_LONG_DOUBLE`	`long double`
`REAL`	`C_FLOAT128`	`__float128`	Ext.
`COMPLEX`	`C_FLOAT_COMPLEX`	`float _Complex`
`COMPLEX`	`C_DOUBLE_COMPLEX`	`double _Complex`
`COMPLEX`	`C_LONG_DOUBLE_COMPLEX`	`long double _Complex`
`REAL`	`C_FLOAT128_COMPLEX`	`__float128 _Complex`	Ext.
`LOGICAL`	`C_BOOL`	`_Bool`
`CHARACTER`	`C_CHAR`	`char`

Additionally, the following parameters of type CHARACTER(KIND=C_CHAR) are defined.

Name	C definition	Value
`C_NULL_CHAR`	null character	`'\0'`
`C_ALERT`	alert	`'\a'`
`C_BACKSPACE`	backspace	`'\b'`
`C_FORM_FEED`	form feed	`'\f'`
`C_NEW_LINE`	new line	`'\n'`
`C_CARRIAGE_RETURN`	carriage return	`'\r'`
`C_HORIZONTAL_TAB`	horizontal tab	`'\t'`
`C_VERTICAL_TAB`	vertical tab	`'\v'`

Moreover, the following two named constants are defined:

Name	Type
`C_NULL_PTR`	`C_PTR`
`C_NULL_FUNPTR`	`C_FUNPTR`

Both are equivalent to the value NULL in C.

10.2 ISO_C_BINDING

10.2 `ISO_C_BINDING`