glib/docs.c

/*
 * Copyright © 2011 Red Hat, Inc
 *
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Matthias Clasen
 */


/* This file collects documentation for macros, typedefs and
 * the like, which have no good home in any of the 'real' source
 * files.
 */

/* Type conversion {{{1 */

/**
 * GINT_TO_POINTER:
 * @i: integer to stuff into a pointer
 *
 * Stuffs an integer into a pointer type.
 *
 * Remember, you may not store pointers in integers. This is not portable
 * in any way, shape or form. These macros only allow storing integers in
 * pointers, and only preserve 32 bits of the integer; values outside the
 * range of a 32-bit integer will be mangled.
 */

/**
 * GPOINTER_TO_INT:
 * @p: pointer containing an integer
 *
 * Extracts an integer from a pointer. The integer must have
 * been stored in the pointer with GINT_TO_POINTER().
 *
 * Remember, you may not store pointers in integers. This is not portable
 * in any way, shape or form. These macros only allow storing integers in
 * pointers, and only preserve 32 bits of the integer; values outside the
 * range of a 32-bit integer will be mangled.
 */

/**
 * GUINT_TO_POINTER:
 * @u: unsigned integer to stuff into the pointer
 *
 * Stuffs an unsigned integer into a pointer type.
 */

/**
 * GPOINTER_TO_UINT:
 * @p: pointer to extract an unsigned integer from
 *
 * Extracts an unsigned integer from a pointer. The integer must have
 * been stored in the pointer with GUINT_TO_POINTER().
 */

/**
 * GSIZE_TO_POINTER:
 * @s: #gsize to stuff into the pointer
 *
 * Stuffs a #gsize into a pointer type.
 *
 * Remember, you may not store pointers in integers. This is not portable
 * in any way, shape or form. These macros only allow storing integers in
 * pointers, and preserve all bits of a pointer (e.g. on CHERI systems).
 * The only types that can store pointers as well as integers are #guintptr
 * and #gintptr.
 */

/**
 * GPOINTER_TO_SIZE:
 * @p: pointer to extract a #gsize from
 *
 * Extracts a #gsize from a pointer. The #gsize must have
 * been stored in the pointer with GSIZE_TO_POINTER().
 *
 * Remember, you may not store pointers in integers. This is not portable
 * in any way, shape or form. These macros only allow storing integers in
 * pointers, and preserve all bits of a pointer (e.g. on CHERI systems).
 * The only types that can store pointers as well as integers are #guintptr
 * and #gintptr.
 *
 * See also GPOINTER_TO_TYPE() for #GType.
 */
 
/* Byte order {{{1 */

/**
 * G_BYTE_ORDER:
 *
 * The host byte order.
 * This can be either %G_LITTLE_ENDIAN or %G_BIG_ENDIAN (support for
 * %G_PDP_ENDIAN may be added in future.)
 */

/**
 * G_LITTLE_ENDIAN:
 *
 * Specifies one of the possible types of byte order.
 * See %G_BYTE_ORDER.
 */

/**
 * G_BIG_ENDIAN:
 *
 * Specifies one of the possible types of byte order.
 * See %G_BYTE_ORDER.
 */

/**
 * G_PDP_ENDIAN:
 *
 * Specifies one of the possible types of byte order
 * (currently unused). See %G_BYTE_ORDER.
 */

/**
 * g_htonl:
 * @val: a 32-bit integer value in host byte order
 *
 * Converts a 32-bit integer value from host to network byte order.
 *
 * Returns: @val converted to network byte order
 */

/**
 * g_htons:
 * @val: a 16-bit integer value in host byte order
 *
 * Converts a 16-bit integer value from host to network byte order.
 *
 * Returns: @val converted to network byte order
 */

/**
 * g_ntohl:
 * @val: a 32-bit integer value in network byte order
 *
 * Converts a 32-bit integer value from network to host byte order.
 *
 * Returns: @val converted to host byte order.
 */

/**
 * g_ntohs:
 * @val: a 16-bit integer value in network byte order
 *
 * Converts a 16-bit integer value from network to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT_FROM_BE:
 * @val: a #gint value in big-endian byte order
 *
 * Converts a #gint value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT_FROM_LE:
 * @val: a #gint value in little-endian byte order
 *
 * Converts a #gint value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT_TO_BE:
 * @val: a #gint value in host byte order
 *
 * Converts a #gint value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian byte order
 */

/**
 * GINT_TO_LE:
 * @val: a #gint value in host byte order
 *
 * Converts a #gint value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian byte order
 */

/**
 * GUINT_FROM_BE:
 * @val: a #guint value in big-endian byte order
 *
 * Converts a #guint value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT_FROM_LE:
 * @val: a #guint value in little-endian byte order
 *
 * Converts a #guint value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT_TO_BE:
 * @val: a #guint value in host byte order
 *
 * Converts a #guint value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian byte order
 */

/**
 * GUINT_TO_LE:
 * @val: a #guint value in host byte order
 *
 * Converts a #guint value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian byte order.
 */

/**
 * GLONG_FROM_BE:
 * @val: a #glong value in big-endian byte order
 *
 * Converts a #glong value from big-endian to the host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GLONG_FROM_LE:
 * @val: a #glong value in little-endian byte order
 *
 * Converts a #glong value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GLONG_TO_BE:
 * @val: a #glong value in host byte order
 *
 * Converts a #glong value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian byte order
 */

/**
 * GLONG_TO_LE:
 * @val: a #glong value in host byte order
 *
 * Converts a #glong value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GULONG_FROM_BE:
 * @val: a #gulong value in big-endian byte order
 *
 * Converts a #gulong value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GULONG_FROM_LE:
 * @val: a #gulong value in little-endian byte order
 *
 * Converts a #gulong value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GULONG_TO_BE:
 * @val: a #gulong value in host byte order
 *
 * Converts a #gulong value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GULONG_TO_LE:
 * @val: a #gulong value in host byte order
 *
 * Converts a #gulong value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GSIZE_FROM_BE:
 * @val: a #gsize value in big-endian byte order
 *
 * Converts a #gsize value from big-endian to the host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GSIZE_FROM_LE:
 * @val: a #gsize value in little-endian byte order
 *
 * Converts a #gsize value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GSIZE_TO_BE:
 * @val: a #gsize value in host byte order
 *
 * Converts a #gsize value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian byte order
 */

/**
 * GSIZE_TO_LE:
 * @val: a #gsize value in host byte order
 *
 * Converts a #gsize value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GSSIZE_FROM_BE:
 * @val: a #gssize value in big-endian byte order
 *
 * Converts a #gssize value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GSSIZE_FROM_LE:
 * @val: a #gssize value in little-endian byte order
 *
 * Converts a #gssize value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GSSIZE_TO_BE:
 * @val: a #gssize value in host byte order
 *
 * Converts a #gssize value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GSSIZE_TO_LE:
 * @val: a #gssize value in host byte order
 *
 * Converts a #gssize value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GINT16_FROM_BE:
 * @val: a #gint16 value in big-endian byte order
 *
 * Converts a #gint16 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT16_FROM_LE:
 * @val: a #gint16 value in little-endian byte order
 *
 * Converts a #gint16 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT16_TO_BE:
 * @val: a #gint16 value in host byte order
 *
 * Converts a #gint16 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GINT16_TO_LE:
 * @val: a #gint16 value in host byte order
 *
 * Converts a #gint16 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GUINT16_FROM_BE:
 * @val: a #guint16 value in big-endian byte order
 *
 * Converts a #guint16 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT16_FROM_LE:
 * @val: a #guint16 value in little-endian byte order
 *
 * Converts a #guint16 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT16_TO_BE:
 * @val: a #guint16 value in host byte order
 *
 * Converts a #guint16 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GUINT16_TO_LE:
 * @val: a #guint16 value in host byte order
 *
 * Converts a #guint16 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GINT32_FROM_BE:
 * @val: a #gint32 value in big-endian byte order
 *
 * Converts a #gint32 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT32_FROM_LE:
 * @val: a #gint32 value in little-endian byte order
 *
 * Converts a #gint32 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT32_TO_BE:
 * @val: a #gint32 value in host byte order
 *
 * Converts a #gint32 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GINT32_TO_LE:
 * @val: a #gint32 value in host byte order
 *
 * Converts a #gint32 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GUINT32_FROM_BE:
 * @val: a #guint32 value in big-endian byte order
 *
 * Converts a #guint32 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT32_FROM_LE:
 * @val: a #guint32 value in little-endian byte order
 *
 * Converts a #guint32 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT32_TO_BE:
 * @val: a #guint32 value in host byte order
 *
 * Converts a #guint32 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GUINT32_TO_LE:
 * @val: a #guint32 value in host byte order
 *
 * Converts a #guint32 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GINT64_FROM_BE:
 * @val: a #gint64 value in big-endian byte order
 *
 * Converts a #gint64 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT64_FROM_LE:
 * @val: a #gint64 value in little-endian byte order
 *
 * Converts a #gint64 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GINT64_TO_BE:
 * @val: a #gint64 value in host byte order
 *
 * Converts a #gint64 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GINT64_TO_LE:
 * @val: a #gint64 value in host byte order
 *
 * Converts a #gint64 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GUINT64_FROM_BE:
 * @val: a #guint64 value in big-endian byte order
 *
 * Converts a #guint64 value from big-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT64_FROM_LE:
 * @val: a #guint64 value in little-endian byte order
 *
 * Converts a #guint64 value from little-endian to host byte order.
 *
 * Returns: @val converted to host byte order
 */

/**
 * GUINT64_TO_BE:
 * @val: a #guint64 value in host byte order
 *
 * Converts a #guint64 value from host byte order to big-endian.
 *
 * Returns: @val converted to big-endian
 */

/**
 * GUINT64_TO_LE:
 * @val: a #guint64 value in host byte order
 *
 * Converts a #guint64 value from host byte order to little-endian.
 *
 * Returns: @val converted to little-endian
 */

/**
 * GUINT16_SWAP_BE_PDP:
 * @val: a #guint16 value in big-endian or pdp-endian byte order
 *
 * Converts a #guint16 value between big-endian and pdp-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT16_SWAP_LE_BE:
 * @val: a #guint16 value in little-endian or big-endian byte order
 *
 * Converts a #guint16 value between little-endian and big-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT16_SWAP_LE_PDP:
 * @val: a #guint16 value in little-endian or pdp-endian byte order
 *
 * Converts a #guint16 value between little-endian and pdp-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT32_SWAP_BE_PDP:
 * @val: a #guint32 value in big-endian or pdp-endian byte order
 *
 * Converts a #guint32 value between big-endian and pdp-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT32_SWAP_LE_BE:
 * @val: a #guint32 value in little-endian or big-endian byte order
 *
 * Converts a #guint32 value between little-endian and big-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT32_SWAP_LE_PDP:
 * @val: a #guint32 value in little-endian or pdp-endian byte order
 *
 * Converts a #guint32 value between little-endian and pdp-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */

/**
 * GUINT64_SWAP_LE_BE:
 * @val: a #guint64 value in little-endian or big-endian byte order
 *
 * Converts a #guint64 value between little-endian and big-endian byte order.
 * The conversion is symmetric so it can be used both ways.
 *
 * Returns: @val converted to the opposite byte order
 */
 
/* Bounds-checked integer arithmetic {{{1 */

/**
 * g_uint_checked_add
 * @dest: a pointer to the #guint destination
 * @a: the #guint left operand
 * @b: the #guint right operand
 *
 * Performs a checked addition of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */

/**
 * g_uint_checked_mul
 * @dest: a pointer to the #guint destination
 * @a: the #guint left operand
 * @b: the #guint right operand
 *
 * Performs a checked multiplication of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */

/**
 * g_uint64_checked_add
 * @dest: a pointer to the #guint64 destination
 * @a: the #guint64 left operand
 * @b: the #guint64 right operand
 *
 * Performs a checked addition of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */

/**
 * g_uint64_checked_mul
 * @dest: a pointer to the #guint64 destination
 * @a: the #guint64 left operand
 * @b: the #guint64 right operand
 *
 * Performs a checked multiplication of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */

/**
 * g_size_checked_add
 * @dest: a pointer to the #gsize destination
 * @a: the #gsize left operand
 * @b: the #gsize right operand
 *
 * Performs a checked addition of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */

/**
 * g_size_checked_mul
 * @dest: a pointer to the #gsize destination
 * @a: the #gsize left operand
 * @b: the #gsize right operand
 *
 * Performs a checked multiplication of @a and @b, storing the result in
 * @dest.
 *
 * If the operation is successful, %TRUE is returned.  If the operation
 * overflows then the state of @dest is undefined and %FALSE is
 * returned.
 *
 * Returns: %TRUE if there was no overflow
 * Since: 2.48
 */
/* Numerical Definitions {{{1 */

/**
 * G_IEEE754_FLOAT_BIAS:
 *
 * The bias by which exponents in single-precision floats are offset.
 */

/**
 * G_IEEE754_DOUBLE_BIAS:
 *
 * The bias by which exponents in double-precision floats are offset.
 */

/**
 * GFloatIEEE754:
 * @v_float: the double value
 *
 * The #GFloatIEEE754 and #GDoubleIEEE754 unions are used to access the sign,
 * mantissa and exponent of IEEE floats and doubles. These unions are defined
 * as appropriate for a given platform. IEEE floats and doubles are supported
 * (used for storage) by at least Intel, PPC and Sparc.
 */

/**
 * GDoubleIEEE754:
 * @v_double: the double value
 *
 * The #GFloatIEEE754 and #GDoubleIEEE754 unions are used to access the sign,
 * mantissa and exponent of IEEE floats and doubles. These unions are defined
 * as appropriate for a given platform. IEEE floats and doubles are supported
 * (used for storage) by at least Intel, PPC and Sparc.
 */

/**
 * G_E:
 *
 * The base of natural logarithms.
 */

/**
 * G_LN2:
 *
 * The natural logarithm of 2.
 */

/**
 * G_LN10:
 *
 * The natural logarithm of 10.
 */

/**
 * G_PI:
 *
 * The value of pi (ratio of circle's circumference to its diameter).
 */

/**
 * G_PI_2:
 *
 * Pi divided by 2.
 */

/**
 * G_PI_4:
 *
 * Pi divided by 4.
 */

/**
 * G_SQRT2:
 *
 * The square root of two.
 */

/**
 * G_LOG_2_BASE_10:
 *
 * Multiplying the base 2 exponent by this number yields the base 10 exponent.
 */

/* Macros {{{1 */

/**
 * G_OS_WIN32:
 *
 * This macro is defined only on Windows. So you can bracket
 * Windows-specific code in "\#ifdef G_OS_WIN32".
 */

/**
 * G_OS_UNIX:
 *
 * This macro is defined only on UNIX. So you can bracket
 * UNIX-specific code in "\#ifdef G_OS_UNIX".
 *
 * To detect whether to compile features that require a specific kernel
 * or operating system, check for the appropriate OS-specific predefined
 * macros instead, for example:
 *
 * - Linux kernel (any libc, including glibc, musl or Android): `\#ifdef __linux__`
 * - Linux kernel and GNU user-space: `\#if defined(__linux__) && defined(__GLIBC__)`
 * - FreeBSD kernel (any libc, including glibc): `\#ifdef __FreeBSD_kernel__`
 * - FreeBSD kernel and user-space: `\#ifdef __FreeBSD__`
 * - Apple operating systems (macOS, iOS, tvOS), regardless of whether
 *   Cocoa/Carbon toolkits are available: `\#ifdef __APPLE__`
 *
 * See <https://sourceforge.net/p/predef/wiki/OperatingSystems/> for more.
 */

/**
 * G_DIR_SEPARATOR:
 *
 * The directory separator character.
 * This is '/' on UNIX machines and '\' under Windows.
 */

/**
 * G_DIR_SEPARATOR_S:
 *
 * The directory separator as a string.
 * This is "/" on UNIX machines and "\" under Windows.
 */

/**
 * G_IS_DIR_SEPARATOR:
 * @c: a character
 *
 * Checks whether a character is a directory
 * separator. It returns %TRUE for '/' on UNIX
 * machines and for '\' or '/' under Windows.
 *
 * Since: 2.6
 */

/**
 * G_SEARCHPATH_SEPARATOR:
 *
 * The search path separator character.
 * This is ':' on UNIX machines and ';' under Windows.
 */

/**
 * G_SEARCHPATH_SEPARATOR_S:
 *
 * The search path separator as a string.
 * This is ":" on UNIX machines and ";" under Windows.
 */

/**
 * TRUE:
 *
 * Defines the %TRUE value for the #gboolean type.
 */

/**
 * FALSE:
 *
 * Defines the %FALSE value for the #gboolean type.
 */

/**
 * NULL:
 *
 * Defines the standard %NULL pointer.
 */

/**
 * MIN:
 * @a: a numeric value
 * @b: a numeric value
 *
 * Calculates the minimum of @a and @b.
 *
 * Returns: the minimum of @a and @b.
 */

/**
 * MAX:
 * @a: a numeric value
 * @b: a numeric value
 *
 * Calculates the maximum of @a and @b.
 *
 * Returns: the maximum of @a and @b.
 */

/**
 * ABS:
 * @a: a numeric value
 *
 * Calculates the absolute value of @a.
 * The absolute value is simply the number with any negative sign taken away.
 *
 * For example,
 * - ABS(-10) is 10.
 * - ABS(10) is also 10.
 *
 * Returns: the absolute value of @a.
 */

/**
 * CLAMP:
 * @x: the value to clamp
 * @low: the minimum value allowed
 * @high: the maximum value allowed
 *
 * Ensures that @x is between the limits set by @low and @high. If @low is
 * greater than @high the result is undefined.
 *
 * For example,
 * - CLAMP(5, 10, 15) is 10.
 * - CLAMP(15, 5, 10) is 10.
 * - CLAMP(20, 15, 25) is 20.
 *
 * Returns: the value of @x clamped to the range between @low and @high
 */

/**
 * G_APPROX_VALUE:
 * @a: a numeric value
 * @b: a numeric value
 * @epsilon: a numeric value that expresses the tolerance between @a and @b
 *
 * Evaluates to a truth value if the absolute difference between @a and @b is
 * smaller than @epsilon, and to a false value otherwise.
 *
 * For example,
 * - `G_APPROX_VALUE (5, 6, 2)` evaluates to true
 * - `G_APPROX_VALUE (3.14, 3.15, 0.001)` evaluates to false
 * - `G_APPROX_VALUE (n, 0.f, FLT_EPSILON)` evaluates to true if `n` is within
 *   the single precision floating point epsilon from zero
 *
 * Returns: %TRUE if the two values are within the desired range
 *
 * Since: 2.58
 */

/**
 * G_STRUCT_MEMBER:
 * @member_type: the type of the struct field
 * @struct_p: a pointer to a struct
 * @struct_offset: the offset of the field from the start of the struct,
 *     in bytes
 *
 * Returns a member of a structure at a given offset, using the given type.
 *
 * Returns: the struct member
 */

/**
 * G_STRUCT_MEMBER_P:
 * @struct_p: a pointer to a struct
 * @struct_offset: the offset from the start of the struct, in bytes
 *
 * Returns an untyped pointer to a given offset of a struct.
 *
 * Returns: an untyped pointer to @struct_p plus @struct_offset bytes
 */

/**
 * G_STRUCT_OFFSET:
 * @struct_type: a structure type, e.g. #GtkWidget
 * @member: a field in the structure, e.g. @window
 *
 * Returns the offset, in bytes, of a member of a struct.
 *
 * Consider using standard C `offsetof()`, available since at least C89
 * and C++98, in new code (but note that `offsetof()` returns a `size_t`
 * rather than a `long`).
 *
 * Returns: the offset of @member from the start of @struct_type,
 *  as a value of type #glong.
 */

/**
 * G_N_ELEMENTS:
 * @arr: the array
 *
 * Determines the number of elements in an array. The array must be
 * declared so the compiler knows its size at compile-time; this
 * macro will not work on an array allocated on the heap, only static
 * arrays or arrays on the stack.
 */

/* Miscellaneous Macros {{{1 */

/**
 * G_STMT_START:
 *
 * Used within multi-statement macros so that they can be used in places
 * where only one statement is expected by the compiler.
 */

/**
 * G_STMT_END:
 *
 * Used within multi-statement macros so that they can be used in places
 * where only one statement is expected by the compiler.
 */

/**
 * G_BEGIN_DECLS:
 *
 * Used (along with %G_END_DECLS) to bracket header files. If the
 * compiler in use is a C++ compiler, adds extern "C"
 * around the header.
 */

/**
 * G_END_DECLS:
 *
 * Used (along with %G_BEGIN_DECLS) to bracket header files. If the
 * compiler in use is a C++ compiler, adds extern "C"
 * around the header.
 */

/**
 * G_VA_COPY:
 * @ap1: the va_list variable to place a copy of @ap2 in
 * @ap2: a va_list
 *
 * Portable way to copy va_list variables.
 *
 * In order to use this function, you must include string.h yourself,
 * because this macro may use memmove() and GLib does not include
 * string.h for you.
 *
 * Each invocation of `G_VA_COPY (ap1, ap2)` must be matched with a
 * corresponding `va_end (ap1)` call in the same function.
 *
 * This is equivalent to standard C `va_copy()`, available since C99
 * and C++11, which should be preferred in new code.
 */

/**
 * G_STRINGIFY:
 * @macro_or_string: a macro or a string
 *
 * Accepts a macro or a string and converts it into a string after
 * preprocessor argument expansion. For example, the following code:
 *
 * |[<!-- language="C" -->
 * #define AGE 27
 * const gchar *greeting = G_STRINGIFY (AGE) " today!";
 * ]|
 *
 * is transformed by the preprocessor into (code equivalent to):
 *
 * |[<!-- language="C" -->
 * const gchar *greeting = "27 today!";
 * ]|
 */

/**
 * G_PASTE:
 * @identifier1: an identifier
 * @identifier2: an identifier
 *
 * Yields a new preprocessor pasted identifier
 * @identifier1identifier2 from its expanded
 * arguments @identifier1 and @identifier2. For example,
 * the following code:
 * |[<!-- language="C" -->
 * #define GET(traveller,method) G_PASTE(traveller_get_, method) (traveller)
 * const gchar *name = GET (traveller, name);
 * const gchar *quest = GET (traveller, quest);
 * GdkColor *favourite = GET (traveller, favourite_colour);
 * ]|
 *
 * is transformed by the preprocessor into:
 * |[<!-- language="C" -->
 * const gchar *name = traveller_get_name (traveller);
 * const gchar *quest = traveller_get_quest (traveller);
 * GdkColor *favourite = traveller_get_favourite_colour (traveller);
 * ]|
 *
 * Since: 2.20
 */

/**
 * G_STATIC_ASSERT:
 * @expr: a constant expression
 *
 * The G_STATIC_ASSERT() macro lets the programmer check
 * a condition at compile time, the condition needs to
 * be compile time computable. The macro can be used in
 * any place where a typedef is valid.
 *
 * A typedef is generally allowed in exactly the same places that
 * a variable declaration is allowed. For this reason, you should
 * not use G_STATIC_ASSERT() in the middle of blocks of code.
 *
 * The macro should only be used once per source code line.
 *
 * Since: 2.20
 */

/**
 * G_STATIC_ASSERT_EXPR:
 * @expr: a constant expression
 *
 * The G_STATIC_ASSERT_EXPR() macro lets the programmer check
 * a condition at compile time. The condition needs to be
 * compile time computable.
 *
 * Unlike G_STATIC_ASSERT(), this macro evaluates to an expression
 * and, as such, can be used in the middle of other expressions.
 * Its value should be ignored. This can be accomplished by placing
 * it as the first argument of a comma expression.
 *
 * |[<!-- language="C" -->
 * #define ADD_ONE_TO_INT(x) \
 *   (G_STATIC_ASSERT_EXPR(sizeof (x) == sizeof (int)), ((x) + 1))
 * ]|
 *
 * Since: 2.30
 */

/**
 * G_GNUC_EXTENSION:
 *
 * Expands to __extension__ when gcc is used as the compiler. This simply
 * tells gcc not to warn about the following non-standard code when compiling
 * with the `-pedantic` option.
 */

/**
 * G_GNUC_CHECK_VERSION:
 * @major: major version to check against
 * @minor: minor version to check against
 *
 * Expands to a check for a compiler with __GNUC__ defined and a version
 * greater than or equal to the major and minor numbers provided. For example,
 * the following would only match on compilers such as GCC 4.8 or newer.
 *
 * |[<!-- language="C" -->
 * #if G_GNUC_CHECK_VERSION(4, 8)
 * #endif
 * ]|
 *
 * Since: 2.42
 */

/**
 * G_GNUC_BEGIN_IGNORE_DEPRECATIONS:
 *
 * Tells gcc (if it is a new enough version) to temporarily stop emitting
 * warnings when functions marked with %G_GNUC_DEPRECATED or
 * %G_GNUC_DEPRECATED_FOR are called. This is useful for when you have
 * one deprecated function calling another one, or when you still have
 * regression tests for deprecated functions.
 *
 * Use %G_GNUC_END_IGNORE_DEPRECATIONS to begin warning again. (If you
 * are not compiling with `-Wdeprecated-declarations` then neither macro
 * has any effect.)
 *
 * This macro can be used either inside or outside of a function body,
 * but must appear on a line by itself. Both this macro and the corresponding
 * %G_GNUC_END_IGNORE_DEPRECATIONS are considered statements, so they
 * should not be used around branching or loop conditions; for instance,
 * this use is invalid:
 *
 * |[<!-- language="C" -->
 *   G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 *   if (check == some_deprecated_function ())
 *   G_GNUC_END_IGNORE_DEPRECATIONS
 *     {
 *       do_something ();
 *     }
 * ]|
 *
 * and you should move the deprecated section outside the condition
 *
 * |[<!-- language="C" -->
 *
 *   // Solution A
 *   some_data_t *res;
 *
 *   G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 *   res = some_deprecated_function ();
 *   G_GNUC_END_IGNORE_DEPRECATIONS
 *
 *   if (check == res)
 *     {
 *       do_something ();
 *     }
 *
 *   // Solution B
 *   G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 *   if (check == some_deprecated_function ())
 *     {
 *       do_something ();
 *     }
 *   G_GNUC_END_IGNORE_DEPRECATIONS
 * ]|
 *
 * |[<!-- language="C" -->
 * static void
 * test_deprecated_function (void)
 * {
 *   G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 *   g_assert_cmpint (my_mistake (), ==, 42);
 *   G_GNUC_END_IGNORE_DEPRECATIONS
 * }
 * ]|
 *
 * Since: 2.32
 */

/**
 * G_GNUC_END_IGNORE_DEPRECATIONS:
 *
 * Undoes the effect of %G_GNUC_BEGIN_IGNORE_DEPRECATIONS, telling
 * gcc to begin outputting warnings again (assuming those warnings
 * had been enabled to begin with).
 *
 * This macro can be used either inside or outside of a function body,
 * but must appear on a line by itself.
 *
 * Since: 2.32
 */

/**
 * G_DEPRECATED:
 *
 * This macro is similar to %G_GNUC_DEPRECATED, and can be used to mark
 * functions declarations as deprecated. Unlike %G_GNUC_DEPRECATED, it is
 * meant to be portable across different compilers and must be placed
 * before the function declaration.
 *
 * |[<!-- language="C" -->
 * G_DEPRECATED
 * int my_mistake (void);
 * ]|
 *
 * Since: 2.32
 */

/**
 * G_DEPRECATED_FOR:
 * @f: the name of the function that this function was deprecated for
 *
 * This macro is similar to %G_GNUC_DEPRECATED_FOR, and can be used to mark
 * functions declarations as deprecated. Unlike %G_GNUC_DEPRECATED_FOR, it
 * is meant to be portable across different compilers and must be placed
 * before the function declaration.
 *
 * |[<!-- language="C" -->
 * G_DEPRECATED_FOR(my_replacement)
 * int my_mistake (void);
 * ]|
 *
 * Since: 2.32
 */

/**
 * G_UNAVAILABLE:
 * @maj: the major version that introduced the symbol
 * @min: the minor version that introduced the symbol
 *
 * This macro can be used to mark a function declaration as unavailable.
 * It must be placed before the function declaration. Use of a function
 * that has been annotated with this macros will produce a compiler warning.
 *
 * Since: 2.32
 */

/**
 * GLIB_DISABLE_DEPRECATION_WARNINGS:
 *
 * A macro that should be defined before including the glib.h header.
 * If it is defined, no compiler warnings will be produced for uses
 * of deprecated GLib APIs.
 */

/**
 * G_GNUC_INTERNAL:
 *
 * This attribute can be used for marking library functions as being used
 * internally to the library only, which may allow the compiler to handle
 * function calls more efficiently. Note that static functions do not need
 * to be marked as internal in this way. See the GNU C documentation for
 * details.
 *
 * When using a compiler that supports the GNU C hidden visibility attribute,
 * this macro expands to __attribute__((visibility("hidden"))).
 * When using the Sun Studio compiler, it expands to __hidden.
 *
 * Note that for portability, the attribute should be placed before the
 * function declaration. While GCC allows the macro after the declaration,
 * Sun Studio does not.
 *
 * |[<!-- language="C" -->
 * G_GNUC_INTERNAL
 * void _g_log_fallback_handler (const gchar    *log_domain,
 *                               GLogLevelFlags  log_level,
 *                               const gchar    *message,
 *                               gpointer        unused_data);
 * ]|
 *
 * Since: 2.6
 */

/**
 * G_C_STD_VERSION:
 *
 * The C standard version the code is compiling against, it's normally
 * defined with the same value of `__STDC_VERSION__` for C standard
 * compatible compilers, while it uses the lowest standard version
 * in pure MSVC, given that in such compiler the definition depends on
 * a compilation flag.
 *
 * This is granted to be undefined when compiling with a C++ compiler.
 *
 * See also: %G_C_STD_CHECK_VERSION and %G_CXX_STD_VERSION
 *
 * Since: 2.76
 */

/**
 * G_C_STD_CHECK_VERSION:
 * @version: The C version to be checked for compatibility
 *
 * Macro to check if the current compiler supports a specified @version
 * of the C standard. Such value must be numeric and can be provided both
 * in the short form for the well-known versions (e.g. `90`, `99`...) or in
 * the complete form otherwise (e.g. `199000L`, `199901L`, `205503L`...).
 *
 * When a C++ compiler is used, the macro is defined and returns always %FALSE.
 *
 * This value is compared against %G_C_STD_VERSION.
 *
 * |[<!-- language="C" -->
 * #if G_C_STD_CHECK_VERSION(17)
 * #endif
 * ]|
 *
 * See also: %G_CXX_STD_CHECK_VERSION
 *
 * Returns: %TRUE if @version is supported by the compiler, %FALSE otherwise
 *
 * Since: 2.76
 */

/**
 * G_CXX_STD_VERSION:
 *
 * The C++ standard version the code is compiling against, it's defined
 * with the same value of `__cplusplus` for C++ standard compatible
 * compilers, while it uses `_MSVC_LANG` in MSVC, given that the
 * standard definition depends on a compilation flag in such compiler.
 *
 * This is granted to be undefined when not compiling with a C++ compiler.
 *
 * See also: %G_CXX_STD_CHECK_VERSION and %G_C_STD_VERSION
 *
 * Since: 2.76
 */

/**
 * G_CXX_STD_CHECK_VERSION:
 * @version: The C++ version to be checked for compatibility
 *
 * Macro to check if the current compiler supports a specified @version
 * of the C++ standard. Such value must be numeric and can be provided both
 * in the short form for the well-known versions (e.g. `11`, `17`...) or in
 * the complete form otherwise (e.g. `201103L`, `201703L`, `205503L`...).
 *
 * When a C compiler is used, the macro is defined and returns always %FALSE.
 *
 * This value is compared against %G_CXX_STD_VERSION.
 *
 * |[<!-- language="C" -->
 * #if G_CXX_STD_CHECK_VERSION(20)
 * #endif
 * ]|
 *
 * See also: %G_C_STD_CHECK_VERSION
 *
 * Returns: %TRUE if @version is supported by the compiler, %FALSE otherwise
 *
 * Since: 2.76
 */

/**
 * G_LIKELY:
 * @expr: the expression
 *
 * Hints the compiler that the expression is likely to evaluate to
 * a true value. The compiler may use this information for optimizations.
 *
 * |[<!-- language="C" -->
 * if (G_LIKELY (random () != 1))
 *   g_print ("not one");
 * ]|
 *
 * Returns: the value of @expr
 *
 * Since: 2.2
 */

/**
 * G_UNLIKELY:
 * @expr: the expression
 *
 * Hints the compiler that the expression is unlikely to evaluate to
 * a true value. The compiler may use this information for optimizations.
 *
 * |[<!-- language="C" -->
 * if (G_UNLIKELY (random () == 1))
 *   g_print ("a random one");
 * ]|
 *
 * Returns: the value of @expr
 *
 * Since: 2.2
 */

/**
 * G_STRLOC:
 *
 * Expands to a string identifying the current code position.
 */

/**
 * G_STRFUNC:
 *
 * Expands to a string identifying the current function.
 *
 * Since: 2.4
 */

/**
 * G_HAVE_GNUC_VISIBILITY:
 *
 * Defined to 1 if gcc-style visibility handling is supported.
 */

/* g_auto(), g_autoptr() and helpers {{{1 */

/**
 * g_auto:
 * @TypeName: a supported variable type
 *
 * Helper to declare a variable with automatic cleanup.
 *
 * The variable is cleaned up in a way appropriate to its type when the
 * variable goes out of scope.  The type must support this.
 * The way to clean up the type must have been defined using one of the macros
 * G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC() or G_DEFINE_AUTO_CLEANUP_FREE_FUNC().
 *
 * This feature is only supported on GCC and clang.  This macro is not
 * defined on other compilers and should not be used in programs that
 * are intended to be portable to those compilers.
 *
 * This is meant to be used with stack-allocated structures and
 * non-pointer types.  For the (more commonly used) pointer version, see
 * g_autoptr().
 *
 * This macro can be used to avoid having to do explicit cleanups of
 * local variables when exiting functions.  It often vastly simplifies
 * handling of error conditions, removing the need for various tricks
 * such as `goto out` or repeating of cleanup code.  It is also helpful
 * for non-error cases.
 *
 * Consider the following example:
 *
 * |[
 * GVariant *
 * my_func(void)
 * {
 *   g_auto(GQueue) queue = G_QUEUE_INIT;
 *   g_auto(GVariantBuilder) builder;
 *   g_auto(GStrv) strv;
 *
 *   g_variant_builder_init (&builder, G_VARIANT_TYPE_VARDICT);
 *   strv = g_strsplit("a:b:c", ":", -1);
 *
 *   ...
 *
 *   if (error_condition)
 *     return NULL;
 *
 *   ...
 *
 *   return g_variant_builder_end (&builder);
 * }
 * ]|
 *
 * You must initialize the variable in some way — either by use of an
 * initialiser or by ensuring that an `_init` function will be called on
 * it unconditionally before it goes out of scope.
 *
 * Since: 2.44
 */

/**
 * g_autoptr:
 * @TypeName: a supported variable type
 *
 * Helper to declare a pointer variable with automatic cleanup.
 *
 * The variable is cleaned up in a way appropriate to its type when the
 * variable goes out of scope.  The type must support this.
 * The way to clean up the type must have been defined using the macro
 * G_DEFINE_AUTOPTR_CLEANUP_FUNC().
 *
 * This feature is only supported on GCC and clang.  This macro is not
 * defined on other compilers and should not be used in programs that
 * are intended to be portable to those compilers.
 *
 * This is meant to be used to declare pointers to types with cleanup
 * functions.  The type of the variable is a pointer to @TypeName.  You
 * must not add your own `*`.
 *
 * This macro can be used to avoid having to do explicit cleanups of
 * local variables when exiting functions.  It often vastly simplifies
 * handling of error conditions, removing the need for various tricks
 * such as `goto out` or repeating of cleanup code.  It is also helpful
 * for non-error cases.
 *
 * Consider the following example:
 *
 * |[
 * gboolean
 * check_exists(GVariant *dict)
 * {
 *   g_autoptr(GVariant) dirname, basename = NULL;
 *   g_autofree gchar *path = NULL;
 *
 *   dirname = g_variant_lookup_value (dict, "dirname", G_VARIANT_TYPE_STRING);
 *
 *   if (dirname == NULL)
 *     return FALSE;
 *
 *   basename = g_variant_lookup_value (dict, "basename", G_VARIANT_TYPE_STRING);
 *
 *   if (basename == NULL)
 *     return FALSE;
 *
 *   path = g_build_filename (g_variant_get_string (dirname, NULL),
 *                            g_variant_get_string (basename, NULL),
 *                            NULL);
 *
 *   return g_access (path, R_OK) == 0;
 * }
 * ]|
 *
 * You must initialise the variable in some way — either by use of an
 * initialiser or by ensuring that it is assigned to unconditionally
 * before it goes out of scope.
 *
 * See also g_auto(), g_autofree() and g_steal_pointer().
 *
 * Since: 2.44
 */

/**
 * g_autofree:
 *
 * Macro to add an attribute to pointer variable to ensure automatic
 * cleanup using g_free().
 *
 * This macro differs from g_autoptr() in that it is an attribute supplied
 * before the type name, rather than wrapping the type definition.  Instead
 * of using a type-specific lookup, this macro always calls g_free() directly.
 *
 * This means it's useful for any type that is returned from
 * g_malloc().
 *
 * Otherwise, this macro has similar constraints as g_autoptr(): only
 * supported on GCC and clang, the variable must be initialized, etc.
 *
 * |[
 * gboolean
 * operate_on_malloc_buf (void)
 * {
 *   g_autofree guint8* membuf = NULL;
 *
 *   membuf = g_malloc (8192);
 *
 *   // Some computation on membuf
 *
 *   // membuf will be automatically freed here
 *   return TRUE;
 * }
 * ]|
 *
 * Since: 2.44
 */

/**
 * g_autolist:
 * @TypeName: a supported variable type
 *
 * Helper to declare a list variable with automatic deep cleanup.
 *
 * The list is deeply freed, in a way appropriate to the specified type, when the
 * variable goes out of scope.  The type must support this.
 *
 * This feature is only supported on GCC and clang.  This macro is not
 * defined on other compilers and should not be used in programs that
 * are intended to be portable to those compilers.
 *
 * This is meant to be used to declare lists of a type with a cleanup
 * function.  The type of the variable is a `GList *`.  You
 * must not add your own `*`.
 *
 * This macro can be used to avoid having to do explicit cleanups of
 * local variables when exiting functions.  It often vastly simplifies
 * handling of error conditions, removing the need for various tricks
 * such as `goto out` or repeating of cleanup code.  It is also helpful
 * for non-error cases.
 *
 * See also g_autoslist(), g_autoptr() and g_steal_pointer().
 *
 * Since: 2.56
 */

/**
 * g_autoslist:
 * @TypeName: a supported variable type
 *
 * Helper to declare a singly linked list variable with automatic deep cleanup.
 *
 * The list is deeply freed, in a way appropriate to the specified type, when the
 * variable goes out of scope.  The type must support this.
 *
 * This feature is only supported on GCC and clang.  This macro is not
 * defined on other compilers and should not be used in programs that
 * are intended to be portable to those compilers.
 *
 * This is meant to be used to declare lists of a type with a cleanup
 * function.  The type of the variable is a `GSList *`.  You
 * must not add your own `*`.
 *
 * This macro can be used to avoid having to do explicit cleanups of
 * local variables when exiting functions.  It often vastly simplifies
 * handling of error conditions, removing the need for various tricks
 * such as `goto out` or repeating of cleanup code.  It is also helpful
 * for non-error cases.
 *
 * See also g_autolist(), g_autoptr() and g_steal_pointer().
 *
 * Since: 2.56
 */

/**
 * g_autoqueue:
 * @TypeName: a supported variable type
 *
 * Helper to declare a double-ended queue variable with automatic deep cleanup.
 *
 * The queue is deeply freed, in a way appropriate to the specified type, when the
 * variable goes out of scope.  The type must support this.
 *
 * This feature is only supported on GCC and clang.  This macro is not
 * defined on other compilers and should not be used in programs that
 * are intended to be portable to those compilers.
 *
 * This is meant to be used to declare queues of a type with a cleanup
 * function.  The type of the variable is a `GQueue *`.  You
 * must not add your own `*`.
 *
 * This macro can be used to avoid having to do explicit cleanups of
 * local variables when exiting functions.  It often vastly simplifies
 * handling of error conditions, removing the need for various tricks
 * such as `goto out` or repeating of cleanup code.  It is also helpful
 * for non-error cases.
 *
 * See also g_autolist(), g_autoptr() and g_steal_pointer().
 *
 * Since: 2.62
 */


/**
 * G_DEFINE_AUTOPTR_CLEANUP_FUNC:
 * @TypeName: a type name to define a g_autoptr() cleanup function for
 * @func: the cleanup function
 *
 * Defines the appropriate cleanup function for a pointer type.
 *
 * The function will not be called if the variable to be cleaned up
 * contains %NULL.
 *
 * This will typically be the `_free()` or `_unref()` function for the given
 * type.
 *
 * With this definition, it will be possible to use g_autoptr() with
 * @TypeName.
 *
 * |[
 * G_DEFINE_AUTOPTR_CLEANUP_FUNC(GObject, g_object_unref)
 * ]|
 *
 * This macro should be used unconditionally; it is a no-op on compilers
 * where cleanup is not supported.
 *
 * Since: 2.44
 */

/**
 * G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC:
 * @TypeName: a type name to define a g_auto() cleanup function for
 * @func: the clear function
 *
 * Defines the appropriate cleanup function for a type.
 *
 * This will typically be the `_clear()` function for the given type.
 *
 * With this definition, it will be possible to use g_auto() with
 * @TypeName.
 *
 * |[
 * G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC(GQueue, g_queue_clear)
 * ]|
 *
 * This macro should be used unconditionally; it is a no-op on compilers
 * where cleanup is not supported.
 *
 * Since: 2.44
 */

/**
 * G_DEFINE_AUTO_CLEANUP_FREE_FUNC:
 * @TypeName: a type name to define a g_auto() cleanup function for
 * @func: the free function
 * @none: the "none" value for the type
 *
 * Defines the appropriate cleanup function for a type.
 *
 * With this definition, it will be possible to use g_auto() with
 * @TypeName.
 *
 * This function will be rarely used.  It is used with pointer-based
 * typedefs and non-pointer types where the value of the variable
 * represents a resource that must be freed.  Two examples are #GStrv
 * and file descriptors.
 *
 * @none specifies the "none" value for the type in question.  It is
 * probably something like %NULL or `-1`.  If the variable is found to
 * contain this value then the free function will not be called.
 *
 * |[
 * G_DEFINE_AUTO_CLEANUP_FREE_FUNC(GStrv, g_strfreev, NULL)
 * ]|
 *
 * This macro should be used unconditionally; it is a no-op on compilers
 * where cleanup is not supported.
 *
 * Since: 2.44
 */

/* Windows Compatibility Functions {{{1 */

/**
 * MAXPATHLEN:
 *
 * Provided for UNIX emulation on Windows; equivalent to UNIX
 * macro %MAXPATHLEN, which is the maximum length of a filename
 * (including full path).
 */

/**
 * G_WIN32_DLLMAIN_FOR_DLL_NAME:
 * @static: empty or "static"
 * @dll_name: the name of the (pointer to the) char array where
 *     the DLL name will be stored. If this is used, you must also
 *     include `windows.h`. If you need a more complex DLL entry
 *     point function, you cannot use this
 *
 * On Windows, this macro defines a DllMain() function that stores
 * the actual DLL name that the code being compiled will be included in.
 *
 * On non-Windows platforms, expands to nothing.
 */

/**
 * G_WIN32_HAVE_WIDECHAR_API:
 *
 * On Windows, this macro defines an expression which evaluates to
 * %TRUE if the code is running on a version of Windows where the wide
 * character versions of the Win32 API functions, and the wide character
 * versions of the C library functions work. (They are always present in
 * the DLLs, but don't work on Windows 9x and Me.)
 *
 * On non-Windows platforms, it is not defined.
 *
 * Since: 2.6
 */


/**
 * G_WIN32_IS_NT_BASED:
 *
 * On Windows, this macro defines an expression which evaluates to
 * %TRUE if the code is running on an NT-based Windows operating system.
 *
 * On non-Windows platforms, it is not defined.
 *
 * Since: 2.6
 */
 
 /* Epilogue {{{1 */
/* vim: set foldmethod=marker: */