home *** CD-ROM | disk | FTP | other *** search
- crash(1L) Version 2.0 08/11/88
-
- Introduction
-
- Crash is a utility for examining kernel tables while the system is
- running, or if there is a facility for taking crash dumps, examining the
- system after it has crashed. SCO does not provide a crash dump facility
- at this time, so that functionality is not present.
-
- The kernel structures which can be examined at present are:
-
- block buffer headers
- open file table entries
- active inode table entries
- mounted file system table entries
- process table entries
- system statistics such as name, version, age
- active and sticky bit text table entries
- tty structures
- system namelist
- per process user page information
- tunable parameters
- arbitrary kernel memory addresses
-
- Using this information, it is possible to determine what files a given
- process is using, what device they reside on, who owns them and where
- the file pointer is currently positioned. Other information on running
- processes may also be determined.
-
- This version of crash differs from most other versions, such as that
- produced by AT&T for their UNIX(tm) systems, in that swapped user pages
- may be printed and the name for swapped processes is given. Also, not
- all of the aliases which are listed in the manual page from AT&T are
- provided. A number of commands have been left out, and some of the
- options for the included commands have been omitted as well.
-
- Commands
-
- Most commands take a list of table entries, which if not present
- defaults to all elements in the table.
-
- Print Buffer Headers
- Syntax: buf, b
-
- Prints the selected block buffer headers.
-
- Example:
- > buf 0 1 2 3 4
- BUF MAJ MIN BLOCK FLAGS
- 0 001 0047 20925 read done
- 1 001 0037 2817 read done
- 2 001 0050 2801 read done
- 3 001 0037 15175 read done
- 4 001 0050 6 done
-
- Print Open File Table Entries
- Syntax: file, f
-
- Prints the selected open file table entries, with cross references
- to the associated inodes, and the current file pointer.
-
- Example:
- > file 0 1 2 3 4
- SLOT FLAG COUNT INODE OFFSET
- 0 001 R 1 9 0
- 1 003 RW 3 3 18
- 2 003 RW 7 11 26800
- 3 002 W 2 4 169
- 4 001 R 1 8 0
-
- Display Command Summary
- Syntax: help, h, ?
-
- Prints the list of currently available commands and the aliases
- for them.
-
- Example:
- > help
- command summary
-
- buf (b) - buffer headers
- file (f) - open files
- help (h,?) - list commands
- inode (ino,i) - active inodes
- mount (m) - mounted file systems
- proc (p) - active and defunct processes
- quit (q,^D) - exit crash
- stat (s) - crash statistics, age, time
- text (t) - active and sticky bit text segments
- user (u) - user page information
- var (v) - tunable parameters
-
- Display Active Inode Table Entries
- Syntax: inode, ino, i
-
- Prints selected active inode table entries giving device, file
- size, permissions, and owners. Cross referenced from mount and
- file tables.
-
- Example:
- > inode 0 2 6 8 20
- SLOT MAJ MIN INUMB REF LINK UID GID SIZE MODE SMAJ SMIN FLAGS
- 0 001 0050 2 5 13 0 0 464 d---755 - -
- 2 001 0050 44 1 1 3 3 13472 f---700 - - txt
- 6 001 0050 204 1 2 0 0 32 d---777 - - mnt
- 8 001 0050 87 2 1 10 10 0 c---666 0004 0002
- 20 001 0050 471 1 1 3 3 50102 f---711 - - acc txt
-
- Display Mounted File System Table Entries
- Syntax: mount, m
-
- Prints the system entries for mounted on file systems. The
- device, mount point, file system sizes and free blocks and inodes
- are displayed.
-
- Example:
- > mount
- SLOT MAJ MIN INODE BUF VOLUME PACK BLOCKS INODES BFREE IFREE
- 0 1 050 0 10 7163 1808 1237 1251
- 1 1 037 6 230 usr rpp386 34000 17024 1320 14238
- 2 1 047 7 245 22950 15024 5499 9800
- 3 2 064 23 387 1200 320 210 50
-
- Display Process Table Entries
- Syntax: proc, p
-
- Prints selected running and defunct process information. The process
- ids, user ids, CPU usage, scheduling priority and wait event are
- displayed. The process name is determined by locating the user page.
-
- Example:
- > proc 0 1 2 3 4
- SLT ST PID PPID PGRP UID EUID PRI CPU EVENT NAME FLAGS
- 0 s 0 0 0 0 0 0 15 16c5c swapper incore sched
- 1 s 1 0 0 0 0 30 0 eeac init incore text
- 2 s 9389 1 9389 100 100 30 0 ef54 csh incore text
- 3 s 31 1 0 0 0 26 0 5eac logger swapped
- 4 s 30 1 0 0 0 40 0 6000000 update incore text
-
- Exit Crash Command
- Syntax: quit, q, ^D
-
- Exits Crash.
-
- Example:
- > quit
- $
-
- Print System Statics
- Syntax: stat, s
-
- Prints information regarding system name, operating system release, version,
- date of crash, and uptime at time of crash.
-
- Example:
- > stat
- sysname: XENIX
- nodename: rpp386
- release: 2.2.1
- version: SysV
- machine: i80386
- time of crash: Thu Aug 11 11:18:00 1988
- age of system: 35 days, 23 hrs., 7 mins.
-
- Print Text Table Entries
- Syntax: text, t
-
- Prints current text table entries. Cross references to inode number
- and process table entry and gives the number of processes which are
- currently referencing this table entry.
- Example:
- > text 0 1 2 3 4
- SLOT INODE REF LDREF PROC SWAPLO+ SIZE FLAGS
- 0 2 1 1 1 0 0 write
- 1 20 2 1 9 0 0 write
- 2 5 1 1 4 0 0 write
- 3 10 1 0 0 0 0 write
- 4 21 1 1 10 0 0 write
-
- Print Per Process User Page Information
- Syntax: user, u
-
- Prints the user page for the current process or a group of processes.
- The argument is the process table slot. If omitted, the currently
- running process, which will invariably be crash, user page will be
- displayed. Information includes user and system times, user and
- group ids, file I/O, system accounting and open file information.
- Provides a list of currently open files by file table entry number.
-
- Example:
- > user
- PER PROCESS USER AREA:
- USER ID's: uid: 100, gid: 0, real uid: 100, real gid: 0
- PROCESS TIMES: user: 16, sys: 22, child user: 0, child sys: 0
- PROCESS MISC: proc slot: 10, cntrl tty: maj(0) min(0)
- IPC: locks: unlocked
- FILE I/O: user addr: 25703640, file offset: 100665344, bytes: 1892,
- segment: user, umask: 22, ulimit: 2097152
- ACCOUNTING: command: crash, memory: 1987167, type: exec
- start: Thu Aug 11 11:28:10 1988
- OPEN FILES: file desc: 0 1 2 3 4 5
- file slot: 11 13 13 18 19 20
-
- Print Tunable Parameter Information
- Syntax: var, v
-
- Displays the tunable parameter values which were used at the time
- of system generation. Included are number of open files, processes
- per user, inodes, mounts, pure text entries and other related
- information.
-
- Example:
- > var
- buffers 512
- calls 30
- inodes 100
- e_inodes 100
- files 100
- e_files 100
- mounts 8
- e_mounts 8
- procs 60
- e_procs 16
- texts 40
- e_texts 40
- clists 64
- sabufs 64
- maxproc 30
- hashbuf 512
- hashmask 511
-
- Caveats and Features
-
- This release of crash is known to run under SCO Xenix 2.2.3. No other
- ports are presently known of. For the most part, porting to a different
- release of Xenix should be quite painless. The principle changes are
- likely to be in the user area, process table entries, and system namelist
- functions.
-
- None of the options are presently implemented. Commands which have been
- implemented have only one format.
-
- Most of the commands are available as command line options. Use the one
- letter command alias as the command line option. The output defaults
- to what it would be if that one letter alias were issued to crash as a
- command. Multiple flags may be given. When in doubt, read the source.
-