Return to cons CVS log

Up to [Plan 9 NeXT] / lucent / sys / man / 3

Annotation of lucent/sys/man/3/cons, revision 1.1

1.1     ! root        1: .TH CONS 3 
        !             2: .SH NAME
        !             3: cons \- console, clocks, process/process group ids, user, null, klog, stats, lights, noise, sysstat, hz, swap, key, hostowner, hostdomain, authenticate, authcheck, authenticator
        !             4: .SH SYNOPSIS
        !             5: .nf
        !             6: .B bind #c /dev
        !             7: 
        !             8: .B /dev/authcheck
        !             9: .B /dev/authenticate
        !            10: .B /dev/authenticator
        !            11: .B /dev/clock
        !            12: .B /dev/cons
        !            13: .B /dev/consctl
        !            14: .B /dev/cputime
        !            15: .B /dev/hostdomain
        !            16: .B /dev/hostowner
        !            17: .B /dev/hz
        !            18: .B /dev/key
        !            19: .B /dev/klog
        !            20: .B /dev/lights
        !            21: .B /dev/msec
        !            22: .B /dev/noise
        !            23: .B /dev/null
        !            24: .B /dev/pgrpid
        !            25: .B /dev/pid
        !            26: .B /dev/ppid
        !            27: .B /dev/swap
        !            28: .B /dev/sysname
        !            29: .B /dev/sysstat
        !            30: .B /dev/time
        !            31: .B /dev/user
        !            32: .fi
        !            33: .SH DESCRIPTION
        !            34: The console device serves a one-level directory
        !            35: giving access to the console and
        !            36: miscellaneous information.
        !            37: .PP
        !            38: Reading the
        !            39: .B cons
        !            40: file returns characters typed on the keyboard.
        !            41: Normally, characters are buffered to enable erase and kill processing.
        !            42: A control-U,
        !            43: .LR ^U ,
        !            44: typed at the keyboard
        !            45: .I kills
        !            46: the current input line (removes all characters
        !            47: from the buffer of characters
        !            48: not yet read via
        !            49: .BR cons ),
        !            50: and a backspace
        !            51: .I erases
        !            52: the previous non-kill, non-erase character from the input buffer.
        !            53: Killing and erasing only delete characters back to, but not including,
        !            54: the last newline.
        !            55: Characters typed at the keyboard actually produce 16-bit runes (see
        !            56: .IR utf (6)),
        !            57: but the runes are translated into the variable-length
        !            58: .SM UTF
        !            59: encoding (see
        !            60: .IR utf (6))
        !            61: before putting them into the buffer.
        !            62: A
        !            63: .IR read (2)
        !            64: of length greater than zero causes the process to wait until a
        !            65: newline or a
        !            66: .L ^D
        !            67: ends the buffer, and then returns as much of the buffer as the argument
        !            68: to
        !            69: .B read
        !            70: allows, but only up to one complete line.
        !            71: A terminating
        !            72: .L ^D
        !            73: is not put into the buffer.
        !            74: If part of the line remains, the next
        !            75: .B read
        !            76: will return bytes from that remainder and not part of any new line
        !            77: that has been typed since.
        !            78: .PP
        !            79: If
        !            80: the string
        !            81: .B rawon
        !            82: has been written to the
        !            83: .B consctl
        !            84: file and the file is still open,
        !            85: .B cons
        !            86: is in
        !            87: .IR "raw mode" :
        !            88: characters are not echoed as they are typed,
        !            89: backspace and
        !            90: .L ^D
        !            91: are not treated specially,
        !            92: and characters are available to
        !            93: .I read
        !            94: as soon as they are typed.
        !            95: Ordinary mode is reentered when
        !            96: .B rawoff
        !            97: is written to
        !            98: .B consctl
        !            99: or this file is closed.
        !           100: .PP
        !           101: A
        !           102: .I write
        !           103: (see
        !           104: .IR read (2))
        !           105: to
        !           106: .B cons
        !           107: causes the characters to be printed on the console screen.
        !           108: .PP
        !           109: The
        !           110: .B null
        !           111: file throws away anything written to it
        !           112: and always returns zero bytes when read.
        !           113: .PP
        !           114: The
        !           115: .B klog
        !           116: file contains the tail of messages written by kernel logging statements.
        !           117: .PP
        !           118: Writing a number (as plain text) to the
        !           119: .B lights
        !           120: device directs any lights that are available to turn on and off.
        !           121: The bits of the number are mapped to the lights in a processor-dependent way.
        !           122: .PP
        !           123: Writing two blank- or tab-separated numbers to the
        !           124: .B noise
        !           125: device causes the machine to make a tone, if possible.
        !           126: The first number is the frequency, in Hertz, and the second is
        !           127: the duration, in milliseconds.
        !           128: .PP
        !           129: The
        !           130: .B hostdomain
        !           131: file contains the name of the authentication domain that
        !           132: this host belongs to; see
        !           133: .IR auth (6).
        !           134: Only the user named in
        !           135: .B /dev/hostowner
        !           136: may write this.
        !           137: .PP
        !           138: The
        !           139: .B hostowner
        !           140: file contains the name of the user that owns the console device files.
        !           141: The hostowner also has group permissions for any local devices.
        !           142: .PP
        !           143: The
        !           144: .B key
        !           145: file is used to set the DES key used for encryption.
        !           146: Each machine has one key.
        !           147: Only the user named in
        !           148: .B /dev/hostowner
        !           149: may write this.
        !           150: .PP
        !           151: The
        !           152: .B authenticate
        !           153: file is used to authenticate new users to the kernel; see
        !           154: .IR auth (6).
        !           155: After an open, the first read returns a ticket request message
        !           156: of the following form:
        !           157: .EX
        !           158:        char num;
        !           159:        char authid[28];
        !           160:        char authdom[48];
        !           161:        char chal[8];
        !           162:        char hostid[28];
        !           163:        char uid[28];
        !           164: .EE
        !           165: Here
        !           166: .I num
        !           167: is 1,
        !           168: .I authid
        !           169: and
        !           170: .I hostid
        !           171: are the contents of
        !           172: .BR hostowner ,
        !           173: and
        !           174: .I authdom
        !           175: is the contents of
        !           176: .BR hostdomain .
        !           177: .I Chal
        !           178: is an 8 byte random challenge created by the kernel.
        !           179: A subsequent write of a valid ticket encrypted with the key contained in
        !           180: .B key
        !           181: changes the user name of the writing process to the value of
        !           182: .I suid
        !           183: in the ticket.
        !           184: The ticket is of the form:
        !           185: .EX
        !           186:        char num;
        !           187:        char chal[8];
        !           188:        char cuid[28];
        !           189:        char suid[28];
        !           190:        char noncekey[7];
        !           191: .EE
        !           192: The ticket is valid if
        !           193: .I num
        !           194: is 64 and
        !           195: .I chal
        !           196: matches the challenge in the ticket request.
        !           197: Writing an invalid ticket generates an error.
        !           198: A read following a successful write yields an authenticator
        !           199: message of the form:
        !           200: .EX
        !           201:        char num;
        !           202:        char chal[8];
        !           203:        char id[4];
        !           204: .EE
        !           205: The authenticator is encrypted in
        !           206: .I noncekey
        !           207: from the ticket.
        !           208: .I Num
        !           209: is 66,
        !           210: .IR id [0-4]
        !           211: are 0,
        !           212: and
        !           213: .I chal
        !           214: matches the challenge in the original ticket request.
        !           215: .PP
        !           216: The
        !           217: .B authenticator
        !           218: file is used to generate an authenticator from a ticket.
        !           219: One writes a ticket encrypted with the key contained in
        !           220: .BR key ,
        !           221: followed, optionally, by a 4-byte
        !           222: .IR id ;
        !           223: a missing
        !           224: .I id
        !           225: defaults to zero.
        !           226: If the client uid matches the current user, a subsequent read yields
        !           227: an authenticator for that ticket with the given
        !           228: .IR id .
        !           229: .PP
        !           230: The
        !           231: .B authcheck
        !           232: file is used to match authenticators to tickets.
        !           233: A write of an authenticator appended to the end of a ticket
        !           234: succeeds if the ticket is encrypted with
        !           235: the key contained in
        !           236: .BR key ,
        !           237: the ticket's
        !           238: .I num
        !           239: is 65,
        !           240: the authenticator is encrypted with the ticket's
        !           241: .BR noncekey ,
        !           242: the authenticator's and ticket's
        !           243: .IR chal 's
        !           244: match, the authenticator's
        !           245: .I num
        !           246: is 66, and the authenticator's
        !           247: .I id
        !           248: is 0.  Alternatively, the write may consist of ticket, authenticator,
        !           249: .IR chal ,
        !           250: and
        !           251: .IR id ,
        !           252: in which case the given
        !           253: .I chal
        !           254: and
        !           255: .I id
        !           256: must match those of the authenticator.
        !           257: .PP
        !           258: The
        !           259: .B user
        !           260: file contains the name of the user associated with the current process.
        !           261: Any process can change to user
        !           262: .B none
        !           263: by writing
        !           264: .B none
        !           265: to this file.
        !           266: .PP
        !           267: The rest of the files contain (mostly) read-only strings.
        !           268: Each string has a fixed length: a
        !           269: .IR read (2)
        !           270: of more than that gives a result of that fixed length (the result does not
        !           271: include a terminating zero byte);
        !           272: a
        !           273: .I read
        !           274: of less than that length leaves the file offset so the
        !           275: rest of the string (but no more) will be read the next time.
        !           276: To reread the file without closing it,
        !           277: .I seek
        !           278: must be used to reset the offset.
        !           279: When the file contains numeric data, each number is formatted
        !           280: in decimal as an 11-digit number with leading blanks and
        !           281: one trailing blank: twelve bytes total.
        !           282: .PP
        !           283: The
        !           284: .B cputime
        !           285: file holds 6 numbers, containing the time in milliseconds
        !           286: that the current process has spent in user mode, system calls,
        !           287: real elapsed time, and then the time spent, by exited children and their descendants,
        !           288: in user mode, system calls, and real elapsed time.
        !           289: .PP
        !           290: The
        !           291: .B clock
        !           292: file holds two numbers: the number of
        !           293: clock ticks since booting followed by the number of clock ticks
        !           294: in a second.
        !           295: .PP
        !           296: The
        !           297: .B sysname
        !           298: file holds the textual name of the machine, e.g.
        !           299: .BR kremvax ,
        !           300: if known.
        !           301: .PP
        !           302: The
        !           303: .B sysstat
        !           304: file holds 8 numbers:
        !           305: processor number, context switches, interrupts, system calls, page faults,
        !           306: tlb faults, tlb purges, and load average.
        !           307: The load average is in units of milli-CPUs and is decayed over time;
        !           308: the others are total counts from boot time.
        !           309: If the machine is a multiprocessor,
        !           310: .B sysstat
        !           311: holds one line per processor.
        !           312: Writing anything to
        !           313: .B sysstat
        !           314: resets all of the counts on all processors.
        !           315: .PP
        !           316: The
        !           317: .B swap
        !           318: device holds a string of the form
        !           319: .IP
        !           320: .IB m1 / m2
        !           321: .B memory
        !           322: .IB s1 / s2
        !           323: .B swap
        !           324: .PP
        !           325: These give, for each of
        !           326: internal memory and the swapping area,
        !           327: the number of pages used and the total available.
        !           328: These numbers are not blank padded.
        !           329: To turn on swapping, write to
        !           330: .B swap
        !           331: the textual file descriptor number of a file or device on which to swap.
        !           332: See
        !           333: .IR swap (8).
        !           334: .PP
        !           335: The other files served by the
        !           336: .I cons
        !           337: device are all single numbers:
        !           338: .TP 10
        !           339: .B hz
        !           340: frequency of the system clock
        !           341: .TP
        !           342: .B msec
        !           343: number of milliseconds since booting
        !           344: .TP
        !           345: .B pgrpid
        !           346: process group number
        !           347: .TP
        !           348: .B pid
        !           349: process number
        !           350: .TP
        !           351: .B ppid
        !           352: parent's process number
        !           353: .TP
        !           354: .B time
        !           355: number of seconds since the epoch 00:00:00 GMT, Jan. 1, 1970.
        !           356: (Can be written once, to set at boot time.)
        !           357: .SH SEE ALSO
        !           358: .IR bit (3),
        !           359: .IR keyboard (6),
        !           360: .IR auth (6),
        !           361: .IR utf (6),
        !           362: .IR swap (8)
        !           363: .SH SOURCE
        !           364: .B /sys/src/9/port/devcons.c
        !           365: .SH BUGS
        !           366: For debugging, two control-T's followed by a letter
        !           367: generate console output:
        !           368: .L ^T^Tp
        !           369: prints data about processes,
        !           370: .L ^T^Tq
        !           371: prints data about streams,
        !           372: .L ^T^Tm
        !           373: prints data about the mount device,
        !           374: .L ^T^Tb
        !           375: prints data about the bitblt device, and
        !           376: .L ^T^Tx
        !           377: prints data about kernel memory allocation.
        !           378: .PP
        !           379: The system can be rebooted by typing
        !           380: .LR ^T^Tr .

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.