portal(5)portal(5)NAMEportal - a "window to the future" for applications
SYNOPSISDESCRIPTION
This header file is a "window to the future" for applications. It will
help you to:
· Write code that is portable across 32-bit and 64-bit systems,
· Avoid undocumented assumptions about sizes of integral types,
· Write portable code that needs to be explicit about the sizes of
integral types,
· Write code that is portable to a platform which has different sizes
of integral types, and
· Share frequently used macros that are portable across 32-bit and
64-bit systems.
In addition to the macros defined in this file, it includes the header
files (see limits(5)) and (see inttypes(5)).
The following macros are defined in
This macro can be used to create a mask that has one bit set.
bit_num is the position of the bit to set, and type is the data
type of the mask. A -1 is returned in the case of overflow or
underflow.
This macro can be used to set a bit in a mask.
mask is the current value of the mask, bit_num is the position
of the bit to set, and type is the data type of the mask.
This macro can be used to return the bit position
of the sign bit for the specified data type. type is the data
type for which to return the position of the sign bit.
This macro can be used to return a mask for the sign bit for
the specified data type. type is the data type for which to
return the sign bit mask.
This macro can be used to do a sign extension from one
data type to another. value is the current value that is to be
sign-extended. old_type is the current data type of value and
new_type is the new data type of value.
This macro can be used to check if code has been
compiled big or little endian. endian is an integer in which
the result will be returned.
The following macros can be used for print formatting and scan format‐
ting of values of data types that can change in size based upon the
compilation flag Examples of such data types are off_t and fpos_t.
EXAMPLES
The macro in the following example will turn on the high bit in a
64-bit integer.
The macro in the following example will be used to turn on all bits
except the sign bit in a 32-bit integer.
The macro in the following example will turn on the three least signif‐
icant bits of the maximum integer.
The macro in the following example will return the position of the sign
bit in a 32-bit integer.
The macro in the following example will return a sign bit mask for a
32-bit integer.
The macro in the following example will convert the 8-bit integer
stored in a char data type to a 64-bit integer and correctly extend the
sign.
The macro in the following example will store a 1 in endian if the com‐
pilation was big endian; otherwise, it will store a 0 in endian.
AUTHOR
was developed by HP.
FILESSEE ALSOinttypes(5), limits(5), printf(3S), scanf(3S).
portal(5)
