Q40357: Operation of scanf When Using the Width Option in the Format

Article: Q40357
Product(s): See article
Version(s): 5.10   | 5.10
Operating System(s): MS-DOS | OS/2
Keyword(s): ENDUSER | | mspl13_c
Last Modified: 17-MAY-1989

The scanf run-time library function under Microsoft C allows the
specification of the width that you would like to read in from the
input device. Some examples of this width formatting are as follows:

   scanf ("%10s", buffer);   /* read ten chars into buffer[] */
   scanf ("%5d", &i);     /* read five digits of a number into i */

When using width parameters in the format, the first n digits are read
into the address specified.

When used with a character string, the width parameter performs as
follows:

   char buffer[15];
   scanf ("%10s", buffer);

The first 10 characters are read, and a NULL terminator is added to
the end of the string.

When used with an integer or float, scanf always reads the first n
characters (including decimal if in a float) specified with the width
format. Entering Invalid characters (e.g. a decimal in an integer, any
alphabetic character) causes the termination and failure of the read.

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