diff options
Diffstat (limited to 'manual')
| -rw-r--r-- | manual/Makefile | 2 | ||||
| -rw-r--r-- | manual/arith.texi | 2 | ||||
| -rw-r--r-- | manual/stdbit.texi | 206 | ||||
| -rw-r--r-- | manual/time.texi | 2 |
4 files changed, 209 insertions, 3 deletions
diff --git a/manual/Makefile b/manual/Makefile index 877e568bbe..b5fda4a7ae 100644 --- a/manual/Makefile +++ b/manual/Makefile @@ -36,7 +36,7 @@ endif chapters = $(addsuffix .texi, \ intro errno memory ctype string charset locale \ message search pattern io stdio llio filesys \ - pipe socket terminal syslog math arith time \ + pipe socket terminal syslog math arith stdbit time \ resource setjmp signal startup process ipc job \ nss users sysinfo conf crypt debug threads \ dynlink probes tunables) diff --git a/manual/arith.texi b/manual/arith.texi index be24c20493..2b99cd8389 100644 --- a/manual/arith.texi +++ b/manual/arith.texi @@ -1,4 +1,4 @@ -@node Arithmetic, Date and Time, Mathematics, Top +@node Arithmetic, Bit Manipulation, Mathematics, Top @c %MENU% Low level arithmetic functions @chapter Arithmetic Functions diff --git a/manual/stdbit.texi b/manual/stdbit.texi new file mode 100644 index 0000000000..fe41c671d8 --- /dev/null +++ b/manual/stdbit.texi @@ -0,0 +1,206 @@ +@node Bit Manipulation, Date and Time, Arithmetic, Top +@c %MENU% Bit manipulation +@chapter Bit Manipulation + +This chapter contains information about functions and macros for +determining the endianness of integer types and manipulating the bits +of unsigned integers. These functions and macros are from ISO C2X and +are declared in the header file @file{stdbit.h}. + +The following macros describe the endianness of integer types. They +have values that are integer constant expressions. + +@defmac __STDC_ENDIAN_LITTLE__ +This macro represents little-endian storage. +@end defmac + +@defmac __STDC_ENDIAN_BIG__ +This macro represents big-endian storage. +@end defmac + +@defmac __STDC_ENDIAN_NATIVE__ +This macro equals @code{__STDC_ENDIAN_LITTLE__} if integer types are +stored in memory in little-endian format, and equals +@code{__STDC_ENDIAN_BIG__} if integer types are stored in memory in +big-endian format. +@end defmac + +The following functions manipulate the bits of unsigned integers. +Each function family has functions for the types @code{unsigned char}, +@code{unsigned short}, @code{unsigned int}, @code{unsigned long int} +and @code{unsigned long long int}. In addition, there is a +corresponding type-generic macro (not listed below), named the same as +the functions but without any suffix such as @samp{_uc}. The +type-generic macro can only be used with an argument of an unsigned +integer type with a width of 8, 16, 32 or 64 bits. + +@deftypefun {unsigned int} stdc_leading_zeros_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_leading_zeros_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_leading_zeros_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_leading_zeros_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_leading_zeros_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_leading_zeros} functions count the number of leading +(most significant) zero bits in @var{x}, starting from the most +significant bit of the argument type. If @var{x} is zero, they return +the width of @var{x} in bits. +@end deftypefun + +@deftypefun {unsigned int} stdc_leading_ones_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_leading_ones_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_leading_ones_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_leading_ones_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_leading_ones_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_leading_ones} functions count the number of leading +(most significant) one bits in @var{x}, starting from the most +significant bit of the argument type. +@end deftypefun + +@deftypefun {unsigned int} stdc_trailing_zeros_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_trailing_zeros_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_trailing_zeros_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_trailing_zeros_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_trailing_zeros_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_trailing_zeros} functions count the number of trailing +(least significant) zero bits in @var{x}, starting from the least +significant bit of the argument type. If @var{x} is zero, they return +the width of @var{x} in bits. +@end deftypefun + +@deftypefun {unsigned int} stdc_trailing_ones_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_trailing_ones_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_trailing_ones_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_trailing_ones_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_trailing_ones_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_trailing_ones} functions count the number of trailing +(least significant) one bits in @var{x}, starting from the least +significant bit of the argument type. +@end deftypefun + +@deftypefun {unsigned int} stdc_first_leading_zero_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_zero_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_zero_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_zero_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_zero_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_first_leading_zero} functions return the position of +the most significant zero bit in @var{x}, counting from the most +significant bit of @var{x} as 1, or zero if there is no zero bit in +@var{x}. +@end deftypefun + +@deftypefun {unsigned int} stdc_first_leading_one_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_one_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_one_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_one_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_first_leading_one_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_first_leading_one} functions return the position of the +most significant one bit in @var{x}, counting from the most +significant bit of @var{x} as 1, or zero if there is no one bit in +@var{x}. +@end deftypefun + +@deftypefun {unsigned int} stdc_first_trailing_zero_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_zero_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_zero_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_zero_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_zero_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_first_trailing_zero} functions return the position of +the least significant zero bit in @var{x}, counting from the least +significant bit of @var{x} as 1, or zero if there is no zero bit in +@var{x}. +@end deftypefun + +@deftypefun {unsigned int} stdc_first_trailing_one_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_one_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_one_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_one_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_first_trailing_one_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_first_trailing_one} functions return the position of +the least significant one bit in @var{x}, counting from the least +significant bit of @var{x} as 1, or zero if there is no one bit in +@var{x}. +@end deftypefun + +@deftypefun {unsigned int} stdc_count_zeros_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_count_zeros_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_count_zeros_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_count_zeros_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_count_zeros_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_count_zeros} functions count the number of zero bits in +@var{x}. +@end deftypefun + +@deftypefun {unsigned int} stdc_count_ones_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_count_ones_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_count_ones_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_count_ones_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_count_ones_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_count_ones} functions count the number of one bits in +@var{x}. +@end deftypefun + +@deftypefun {_Bool} stdc_has_single_bit_uc (unsigned char @var{x}) +@deftypefunx {_Bool} stdc_has_single_bit_us (unsigned short @var{x}) +@deftypefunx {_Bool} stdc_has_single_bit_ui (unsigned int @var{x}) +@deftypefunx {_Bool} stdc_has_single_bit_ul (unsigned long int @var{x}) +@deftypefunx {_Bool} stdc_has_single_bit_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_has_single_bit} functions return whether @var{x} has +exactly one bit set to one. +@end deftypefun + +@deftypefun {unsigned int} stdc_bit_width_uc (unsigned char @var{x}) +@deftypefunx {unsigned int} stdc_bit_width_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_bit_width_ui (unsigned int @var{x}) +@deftypefunx {unsigned int} stdc_bit_width_ul (unsigned long int @var{x}) +@deftypefunx {unsigned int} stdc_bit_width_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_bit_width} functions return the minimum number of bits +needed to store @var{x}, not counting leading zero bits. If @var{x} +is zero, they return zero. +@end deftypefun + +@deftypefun {unsigned char} stdc_bit_floor_uc (unsigned char @var{x}) +@deftypefunx {unsigned short} stdc_bit_floor_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_bit_floor_ui (unsigned int @var{x}) +@deftypefunx {unsigned long int} stdc_bit_floor_ul (unsigned long int @var{x}) +@deftypefunx {unsigned long long int} stdc_bit_floor_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_bit_floor} functions return the largest integer power +of two that is less than or equal to @var{x}. If @var{x} is zero, +they return zero. +@end deftypefun + +@deftypefun {unsigned char} stdc_bit_ceil_uc (unsigned char @var{x}) +@deftypefunx {unsigned short} stdc_bit_ceil_us (unsigned short @var{x}) +@deftypefunx {unsigned int} stdc_bit_ceil_ui (unsigned int @var{x}) +@deftypefunx {unsigned long int} stdc_bit_ceil_ul (unsigned long int @var{x}) +@deftypefunx {unsigned long long int} stdc_bit_ceil_ull (unsigned long long int @var{x}) +@standards{C2X, stdbit.h} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +The @code{stdc_bit_ceil} functions return the smallest integer power +of two that is greater than or equal to @var{x}. If this cannot be +represented in the return type, they return zero. +@end deftypefun diff --git a/manual/time.texi b/manual/time.texi index d661d55d40..7d9efc7c6f 100644 --- a/manual/time.texi +++ b/manual/time.texi @@ -1,4 +1,4 @@ -@node Date and Time, Resource Usage And Limitation, Arithmetic, Top +@node Date and Time, Resource Usage And Limitation, Bit Manipulation, Top @c %MENU% Functions for getting the date and time and formatting them nicely @chapter Date and Time |