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ABS |
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!!!ABS |
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NAME |
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SYNOPSIS |
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DESCRIPTION |
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RETURN VALUE |
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CONFORMING TO |
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NOTES |
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SEE ALSO |
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---- |
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!!NAME |
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abs, labs, llabs, imaxabs - compute the absolute value of an integer. |
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!!SYNOPSIS |
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__#include |
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__ ''j''__); |
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long int labs(long int__ ''j''__); |
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long long int llabs(long long int__ ''j''__); |
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#include |
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__ ''j''__); |
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__ |
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!!DESCRIPTION |
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The __abs()__ function computes the absolute value of the |
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integer argument ''j''. The __labs()__, __llabs()__ |
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and __imaxabs()__ functions compute the absolute value of |
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the argument ''j'' of the appropriate integer type for |
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the function. |
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!!RETURN VALUE |
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Returns the absolute value of the integer argument, of the |
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appropriate integer type for the function. |
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!!CONFORMING TO |
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SVID 3, POSIX.1, BSD 4.3, ISO/IEC 9899. POSIX.1 (1996 |
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edition) only requires the __abs()__ function. ISO/IEC |
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9899:1990 (C89) only includes the __abs()__ and |
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__labs()__ functions; the functions __llabs()__ and |
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__imaxabs()__ were added in C99. |
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!!NOTES |
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Trying to take the absolute value of the most negative |
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integer is not defined. |
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The __llabs()__ function is included in glibc since |
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version 2.0, but is not in libc5 or libc4. The |
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__imaxabs()__ function is included in glibc since version |
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2.1.1. |
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For __llabs()__ to be declared, it may be necessary to |
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define ___ISOC99_SOURCE__ or ___ISOC9X_SOURCE__ |
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(depending on the version of glibc) before including any |
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standard headers. |
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GCC handles __abs()__ and __labs()__ as builtin |
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functions. GCC 3.0 also handles __llabs()__ and |
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__imaxabs()__ as builtins. |
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!!SEE ALSO |
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ceil(3), floor(3), fabs(3), |
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rint(3) |
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---- |
