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PRINTF(9)		 BSD Kernel Developer's	Manual		     PRINTF(9)

NAME
     printf, uprintf, tprintf -- formatted output conversion

SYNOPSIS
     #include <sys/types.h>
     #include <sys/systm.h>

     int
     printf(const char *fmt, ...);

     void
     tprintf(struct proc *p, int pri, const char *fmt, ...);

     int
     uprintf(const char	*fmt, ...);

DESCRIPTION
     The printf(9) family of functions are similar to the printf(3) family of
     functions.	 The three functions each use a	different output stream.  The
     uprintf() function	outputs	to the current process'	controlling tty, while
     printf() writes to	the console as well as to the logging facility.	 The
     tprintf() function	outputs	to the tty associated with the process p and
     the logging facility if pri is not	-1.

     Each of these related functions use the fmt parameter in the same manner
     as	printf(3).  However, printf(9) adds two	other conversion specifiers.

     The %b identifier expects two arguments: an int and a char	*.  These are
     used as a register	value and a print mask for decoding bitmasks.  The
     print mask	is made	up of two parts: the base and the arguments.  The base
     value is the output base expressed	as an integer value; for example, \10
     gives octal and \20 gives hexadecimal.  The arguments are made up of a
     sequence of bit identifiers.  Each	bit identifier begins with an integer
     value which is the	number of the bit this identifier describes.  The rest
     of	the identifier is a string of characters containing the	name of	the
     bit.  The string is terminated by either the bit number at	the start of
     the next bit identifier or	NUL for	the last bit identifier.

     The %D identifier is meant	to assist in hexdumps.	It requires two	argu-
     ments: a u_char * pointer and a char * string.  The memory	pointed	to be
     the pointer is output in hexadecimal one byte at a	time.  The string is
     used as a delimiter between individual bytes.  If present,	a width	direc-
     tive will specify the number of bytes to display.	By default, 16 bytes
     of	data are output.

RETURN VALUES
     The printf() and the uprintf() functions return the number	of characters
     displayed.

EXAMPLES
     This example demonstrates the use of the %b and %D	conversion specifiers.
     The function

	   void
	   printf_test(void)
	   {

		   printf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
		   printf("out:	%4D\n",	"AAAA",	":");
	   }

     will produce the following	output:

	   reg=3<BITTWO,BITONE>
	   out:	41:41:41:41

SEE ALSO
     printf(3)

BSD				April 25, 2001				   BSD

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | EXAMPLES | SEE ALSO

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