1.\" 2.\" Copyright (c) 2001 Andrew R. Reiter 3.\" Copyright (c) 2004 Joerg Wunsch 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 20.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 21.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 22.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 23.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.\" $FreeBSD: src/share/man/man9/printf.9,v 1.8 2006/09/08 14:05:03 ru Exp $ 28.\" 29.Dd December 21, 2012 30.Dt KPRINTF 9 31.Os 32.Sh NAME 33.Nm kprintf , 34.Nm ksprintf , 35.Nm ksnprintf , 36.Nm kvprintf , 37.Nm kvsprintf , 38.Nm kvsnprintf , 39.Nm krateprintf , 40.Nm tprintf , 41.Nm uprintf , 42.Nm log 43.Nd formatted output conversion 44.Sh SYNOPSIS 45.In sys/types.h 46.In sys/systm.h 47.Ft int 48.Fn kprintf "const char *format" ... 49.Ft int 50.Fn ksprintf "char *str" "const char *format" ... 51.Ft int 52.Fn ksnprintf "char *str" "size_t size" "const char *format" ... 53.Ft int 54.Fn kvprintf "const char *format" "__va_list ap" 55.Ft int 56.Fn kvsprintf "char *str" "const char *format" "__va_list ap" 57.Ft int 58.Fn kvsnprintf "char *str" "size_t size" "const char *format" "__va_list ap" 59.Ft void 60.Fn krateprintf "struct krate *rate" "const char *format" ... 61.Ft int 62.Fn uprintf "const char *format" ... 63.In sys/tprintf.h 64.Ft int 65.Fn tprintf "struct proc *p" "int pri" "const char *format" ... 66.In sys/syslog.h 67.Ft int 68.Fn log "int pri" "const char *format" ... 69.Sh DESCRIPTION 70The 71.Nm 72family of functions are similar to the 73.Xr printf 3 74family of functions. 75The different functions each use a different output stream. 76The 77.Fn uprintf 78function outputs to the current process' controlling tty, while 79.Fn kprintf , 80.Fn ksprintf , 81.Fn ksnprintf , 82.Fn kvprintf , 83.Fn kvsprintf 84and 85.Fn kvsnprintf 86write to the console as well as to the logging facility. 87The 88.Fn tprintf 89function outputs to the tty associated with the process 90.Fa p 91and the logging facility if 92.Fa pri 93is not \-1. 94The 95.Fn log 96function sends the message to the kernel logging facility, using 97the log level as indicated by 98.Fa pri . 99.Pp 100Each of these related functions use the 101.Fa format , 102.Fa str , 103.Fa size 104and 105.Fa va 106parameters in the same manner as 107.Xr printf 3 . 108However, the 109.Nm 110functions add another conversion specifier to 111.Fa format : 112.Pp 113The 114.Cm \&%pb%i 115identifier expects two arguments: an 116.Vt "char *" 117and a 118.Vt int . 119These are used as a register value and a print mask for decoding bitmasks. 120The print mask is made up of two parts: the base and the 121arguments. 122The base value is the output base expressed as an integer value; 123for example, \e10 gives octal and \e20 gives hexadecimal. 124The arguments are made up of a sequence of bit identifiers. 125Each bit identifier begins with an integer value which is the number of the 126bit (starting from 1) this identifier describes. 127The rest of the identifier is a string of characters containing the name of 128the bit. 129The string is terminated by either the bit number at the start of the next 130bit identifier or 131.Dv NUL 132for the last bit identifier. 133.Pp 134The 135.Fn log 136function uses 137.Xr syslog 3 138level values 139.Dv LOG_DEBUG 140through 141.Dv LOG_EMERG 142for its 143.Fa pri 144parameter (mistakenly called 145.Sq priority 146here). 147Alternatively, if a 148.Fa pri 149of \-1 is given, the message will be appended to the last log message 150started by a previous call to 151.Fn log . 152As these messages are generated by the kernel itself, the facility will 153always be 154.Dv LOG_KERN . 155.Pp 156The 157.Fn krateprintf 158function is a rate controlled version of 159.Fn kprintf . 160The 161.Fa freq 162member of the 163.Vt struct krate 164pointed to by 165.Fa rate 166must be initialized with the desired reporting frequency. 167A 168.Fa freq 169of 0 will result in no output. 170Initializing 171.Fa count 172to a negative value allows an initial burst. 173.Sh RETURN VALUES 174The 175.Fn kprintf , 176.Fn ksprintf , 177.Fn ksnprintf , 178.Fn kvprintf , 179.Fn kvsprintf , 180.Fn kvsnprintf , 181.Fn tprintf , 182.Fn uprintf , 183and 184.Fn log 185functions return the number of characters displayed. 186.Sh EXAMPLES 187This example demonstrates the use of the 188.Cm \&%pb%i 189conversion specifier. 190The function 191.Bd -literal -offset indent 192void 193kprintf_test(void) 194{ 195 196 kprintf("reg=%pb%i\en", "\e10\e2BITTWO\e1BITONE\en", 3); 197} 198.Ed 199.Pp 200will produce the following output: 201.Bd -literal -offset indent 202reg=3<BITTWO,BITONE> 203.Ed 204.Pp 205The call 206.Bd -literal -offset indent 207log(LOG_DEBUG, "%s%d: been there.\en", sc->sc_name, sc->sc_unit); 208.Ed 209.Pp 210will add the appropriate debug message at priority 211.Dq Li kern.debug 212to the system log. 213.Sh SEE ALSO 214.Xr printf 3 , 215.Xr syslog 3 216