Formatting and I/O Library Chapter 2
LabWindows/CVI Standard Libraries 2-32 © National Instruments Corporation
Convert the integer value 23 to its ASCII representation and place the contents in a string
variable:
char a[5];
int b,n;
b = 23;
n = Fmt (a, "%s<%i", b);
After the Fmt call, a contains the string 23.
In this example, a is the target argument, b is the source argument, and the string %s<%i is the
format string. The Fmt call uses the format string to determine how to convert the source
argument into the target argument.
With the Scan function, you can convert the string 23 to an integer:
char *a;
a = "23";
n = Scan (a$, "%s>%i", b%);
After the Scan call, b = 23.
In this example, a is the source argument, b is the target argument, and %s>%i is the format
string. In both the formatting and the scanning functions, the format string defines the variable
types of the source and target arguments and the method by which the source arguments are
transformed into the target arguments.
Formatting Functions
The following information is a brief description of the three formatting functions:
•n = Fmt (target, formatstring, source1, ..., sourcen);
The Fmt function formats the source1, ..., sourcen arguments according to
descriptions in the formatstring argument. The function places the result of the
formatting into the target argument.
•n = FmtFile (handle, formatstring, source1, ..., sourcen);
The FmtFile function formats the source1, ..., sourcen arguments according to
descriptions in the formatstring argument. The function writes the result of the
formatting into the file corresponding to the handle argument.
•n = FmtOut (formatstring, source1, ..., sourcen);
The FmtOut function formats the source1, ..., sourcen arguments according to
descriptions in the formatstring argument. The function writes the result of the
formatting to Standard Out.