nl_scanf.3int

来自「<B>Digital的Unix操作系统VAX 4.2源码</B>」· 3INT 代码 · 共 146 行

.TH nl_scanf 3int
.SH Name 
nl_scanf, nl_fscanf, nl_sscanf \- convert formatted input
.SH Syntax 
.B #include <stdio.h>
.PP
.B int nl_scanf (
.I format
[, 
.I pointer
] ...
.B )
.br
.B char
.IR *format ;
.PP
.B int nl_fscanf (
.IR stream ,
.I format 
[,
.I pointer
] ...
.B )
.br
.B FILE 
.IR *stream ;
.br
.B char
.IR *format ;
.PP
.B int nl_sscanf (
.IR s , 
.I format
[,
.I pointer
] ...
.B )
.br
.B char
.IR *s , 
.IR *format ;
.SH Description 
.NXR "nl_scanf subroutine"
.NXR "nl_fscanf subroutine"
.NXR "nl_sscanf subroutine"
The international functions
.PN nl_scanf ,
.PN nl_fscanf ,
and
.PN nl_sscanf 
are identical to and have been superceded by the
international functions
.PN scanf ,
.PN fscanf ,
and
.PN sscanf 
in 
.I libi.
You should use the 
.PN scanf ,
.PN fscanf ,
and
.PN sscanf 
functions when you write new calls to convert formatted input in 
international programs. For more information on these functions, see the 
.MS scanf 3int
reference page.
.PP
You can continue to use existing calls to the  
.PN nl_scanf ,
.PN nl_fscanf ,
or 
.PN nl_sscanf
functions. These functions remain available for compatibility with XPG\-2
conformant software, but may not be supported in future releases of 
the ULTRIX system.
.PP
The 
.PN nl_scanf ,
.PN nl_fscanf ,
and 
.PN nl_sscanf
international functions are similar to the 
.PN scanf 
standard I/O function. (For more information on the 
.PN scanf 
standard I/O function, see 
.MS scanf 3s
reference page.)  The difference is that the international functions 
allow you to use the 
.I %digit$
conversion character in place of the 
.I %
character you use in the standard I/O functions. The 
.I digit
is a decimal digit
.I n 
from 1 to 9.  The international functions apply conversions to the 
.I n
th argument in the argument list, rather than to the next unused
argument.
.PP
You can use the
.I %
conversion character in the international functions.  However, you cannot
mix the 
.I %
conversion character with the
.I %digit$
conversion character in a single call.
.SS International Environment
.IP LC_NUMERIC 15
If this environment is set and valid, 
.PN nl_scanf
uses the international language database named in the definition to
determine radix character rules.
.IP LANG 15
If this environment variable is set and valid 
.PN nl_scanf
uses the international language database named in the definition to
determine collation and character classification rules.  If
.PN LC_NUMERIC 
is defined, its definition supersedes the definition of
LANG.
.SH Examples
The following shows an example of using the
.PN nl_scanf
function:
.EX
nl_scanf("%2$s %1$d", integer, string)
.EE
If the input contains `` january 9 '', the
.PN nl_scanf
function assigns 9 to 
.I integer 
and ``january'' to 
.I string .
.SH Return Values 
These functions return either the number of items matched or EOF on
end of input, along with the number of missing or invalid  data items.
.SH See Also 
intro(3int), setlocale(3), strtod(3), strtol(3), nl_printf(3int), printf(3int), 
scanf(3int), getc(3s), printf(3s), scanf(3s) 
.br
.I Guide to Developing International Software