diff options
Diffstat (limited to 'manual')
| -rw-r--r-- | manual/lang.texi | 18 |
1 files changed, 2 insertions, 16 deletions
diff --git a/manual/lang.texi b/manual/lang.texi index 2a73c723b4..6cb7371aab 100644 --- a/manual/lang.texi +++ b/manual/lang.texi @@ -629,27 +629,13 @@ This is an unsigned integer type used to represent the sizes of objects. The result of the @code{sizeof} operator is of this type, and functions such as @code{malloc} (@pxref{Unconstrained Allocation}) and @code{memcpy} (@pxref{Copying and Concatenation}) accept arguments of -this type to specify object sizes. +this type to specify object sizes. On systems using @theglibc{}, this +will be @w{@code{unsigned int}} or @w{@code{unsigned long int}}. @strong{Usage Note:} @code{size_t} is the preferred way to declare any arguments or variables that hold the size of an object. @end deftp -In the GNU system @code{size_t} is equivalent to either -@w{@code{unsigned int}} or @w{@code{unsigned long int}}. These types -have identical properties on the GNU system and, for most purposes, you -can use them interchangeably. However, they are distinct as data types, -which makes a difference in certain contexts. - -For example, when you specify the type of a function argument in a -function prototype, it makes a difference which one you use. If the -system header files declare @code{malloc} with an argument of type -@code{size_t} and you declare @code{malloc} with an argument of type -@code{unsigned int}, you will get a compilation error if @code{size_t} -happens to be @code{unsigned long int} on your system. To avoid any -possibility of error, when a function argument or value is supposed to -have type @code{size_t}, never declare its type in any other way. - @strong{Compatibility Note:} Implementations of C before the advent of @w{ISO C} generally used @code{unsigned int} for representing object sizes and @code{int} for pointer subtraction results. They did not |