63 lines
1.4 KiB
C
63 lines
1.4 KiB
C
/*
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FUNCTION
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<<assert>>---macro for debugging diagnostics
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INDEX
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assert
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ANSI_SYNOPSIS
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#include <assert.h>
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void assert(int <[expression]>);
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TRAD_SYNOPSIS
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#include <assert.h>
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assert(<[expression]>)
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int <[expression]>;
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DESCRIPTION
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Use this macro to embed debuggging diagnostic statements in
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your programs. The argument <[expression]> should be an
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expression which evaluates to true (nonzero) when your program
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is working as you intended.
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When <[expression]> evaluates to false (zero), <<assert>>
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calls <<abort>>, after first printing a message showing what
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failed and where:
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. Assertion failed: <[expression]>, file <[filename]>, line <[lineno]>
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The macro is defined to permit you to turn off all uses of
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<<assert>> at compile time by defining <<NDEBUG>> as a
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preprocessor variable. If you do this, the <<assert>> macro
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expands to
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. (void(0))
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RETURNS
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<<assert>> does not return a value.
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PORTABILITY
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The <<assert>> macro is required by ANSI, as is the behavior
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when <<NDEBUG>> is defined.
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Supporting OS subroutines required (only if enabled): <<close>>, <<fstat>>,
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<<getpid>>, <<isatty>>, <<kill>>, <<lseek>>, <<read>>, <<sbrk>>, <<write>>.
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*/
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#include <assert.h>
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#include <stdlib.h>
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#include <stdio.h>
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void
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_DEFUN (__assert, (file, line, failedexpr),
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const char *file _AND
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int line _AND
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const char *failedexpr)
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{
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(void)fiprintf(stderr,
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"assertion \"%s\" failed: file \"%s\", line %d\n",
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failedexpr, file, line);
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abort();
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/* NOTREACHED */
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}
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