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+.\" Copyright (C) 2022 Alejandro Colomar <alx@kernel.org>
+.\"
+.\" SPDX-License-Identifier: Linux-man-pages-copyleft
+.\"
+.TH _Generic 3 2023-05-03 "Linux man-pages 6.05.01"
+.SH NAME
+_Generic \- type-generic selection
+.SH SYNOPSIS
+.nf
+.BR _Generic( \fIexpression\fP ", type1: " e1 ", " "... /*" \
+", default: " "e */" );
+.fi
+.SH DESCRIPTION
+.BR _Generic ()
+evaluates the path of code under the type selector
+that is compatible with the type of the controlling
+.IR expression ,
+or
+.B default:
+if no type is compatible.
+.PP
+.I expression
+is not evaluated.
+.PP
+This is especially useful for writing type-generic macros,
+that will behave differently depending on the type of the argument.
+.SH STANDARDS
+C11.
+.SH HISTORY
+C11.
+.SH EXAMPLES
+The following program demonstrates how to write
+a replacement for the standard
+.BR imaxabs (3)
+function, which being a function can't really provide what it promises:
+seamlessly upgrading to the widest available type.
+.IP
+.\" SRC BEGIN (_Generic.c)
+.EX
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+\&
+#define my_imaxabs _Generic(INTMAX_C(0), \e
+ long: labs, \e
+ long long: llabs \e
+ /* long long long: lllabs */ \e
+)
+\&
+int
+main(void)
+{
+ off_t a;
+\&
+ a = \-42;
+ printf("imaxabs(%jd) == %jd\en", (intmax_t) a, my_imaxabs(a));
+ printf("&imaxabs == %p\en", &my_imaxabs);
+ printf("&labs == %p\en", &labs);
+ printf("&llabs == %p\en", &llabs);
+\&
+ exit(EXIT_SUCCESS);
+}
+.EE
+.\" SRC END