- id
- displays the system identity of the user
- lslicense
- list maximum number of users
- last
- information about previous logins
- w
- lists summary of current users
- who
- displays information about all current users
- uname
- displays system info
- type
- shows path location
- whereis
- shows path location
- what
- displays header information about the source file
- whatis
- displays a short description of a function
- basename
- returns the base file name
- ac
- displays connect time
- date
- displays or sets the date
- timex
- displays the elapsed time
|
- cmp
- compares two files
- diff
- compares text files
- head
or tail - display start or end of
file
- od
- dumps the contents of a file
- split
- makes smaller files from a large one
- cut
- cuts out selected text
- tr
- translates characters
- sed
- stream edit command to change text
- nl
- produces an OUTPUT file by inserting the line number
- captoinfo
- converts termcap to terminfo
- nvdmetoa
- convert EBCDIC files to ASCII
- sum
- displays checksum for a file
|
- errclear
- deletes entries in the error log
- errpt
- generates an error report
- diag
- performs hardware problem determinatio
- trace
- kernel debugging
|
- at
- schedules jobs
- batch
- run 1 or more jobs in the background
- nice
- execute a command at a lower priority
- tee
- used to preserve output from a pipeline
|
- find
- finds files with matching expressions
- grep
- searches a file for a pattern
|
|
- kill
- stop a process
- stopsrc
- gracefully shuts down all subsystems
- shutdown
- shutdown system
- fastboot
- restarts the system without running fsck
- fasthalt
- halts the system
|
- lsitab
- list contents of the /etc/inittab file
- rmitab
- removes an entry from the /etc/inittab
- telinit
- forces the init process to re-read the /etc/inittab
|
- strip
- removes symbol table
|
- xargs
- constructs an argument list
|
top
of page
Displays connect
time totals for users
Example:
ac root
Outputs: total 52.80 seconds
top
of page
Schedules
jobs to run at a later date
| Examples |
What
it does |
1)
at 17:00
2) banner CALL HOME > /dev/tty0
3) ^D |
At 5:00
p.m., message CALL HOME is written to terminal tty0 |
1)
at 18:00
2) make -f /u/roger/makefile
3) ^D |
Compiles
files specified in /u/roger/makefile. Results of this compilation
are sent to user's mailbox who initiated the 'at' request. |
| at
-l |
List
jobs in at queue.
root.686858340.a Mon Oct 07 12:59:00 1991 |
| at
-r root.686858340.a |
Removes
a job from at queue.
at file: root.686858340.a deleted |
top
of page
Returns the
base file name of a string
Example:
echo `basename \`pwd\``
Returns the name of the current directory your in. Does
not show the full pathname of that directory.
top
of page
Run 1 or more
jobs in the background. All output will be sent to the mail system.
Jobs submitted are started immediately.
Example:
batch
job1
job2
^D
Note:
Once a batch job starts, it's job number can't be seen
via the at -l because that job is no longer in the batch
queue - it's a running process.
Further,
once a batch job is running, it can't be canceled by the
at -r <job #> command since this only cancels jobs
that are still pending in the batch/at queue.
top
of page
Converts a
termcap source file to a terminfo source file
Example:
captoinfo Wyse150.tc > wyse150.ti
Once the termcap file (*.tc) has been translated to a terminfo
(*.ti) file, compile the .ti file with the tic compiler
(tic wyse150.ti).
top
of page
Compares two
files for differences
Example:
cmp test1 test2
If the files are identical, no message is displayed, else
the first difference is displayed.
top
of page
Cuts out selected
text from a file or environment variable
| Examples |
What
it does |
| echo
`date|cut -d' ' -f2` |
Oct
(returns the month from the date command ) |
| cat
/etc/passwd|cut -d: -f1,3 |
Will
output the 1st and 3rd field delimited by ':' from
the /etc/passwd file:
root:0
daemon:1
bin:2
lpd:104 |
top
of page
Displays or
sets the date/time. Date format is: mmddHHMM.SSyy
Example:
date 02030830.0054 (This sets
the date/time to Feb 03 08:30:00 CST 1954)
top
of page
Performs hardware
problem determination
- FORMAT
& CERTIFY: Writes all of the ID fields and writes a bit
pattern in all of the data fields. Also reassigns data blocks
that are BAD during formatting. If too many BAD BLOCKS, a message
is sent to alert operator. If data resides on the PV being formatted,
it will be removed - lost forever.
- CERTIFY
DISK Reads all ID and data fields. Checks for BAD DATA in the
ID and data fields. If too many BAD BLOCKS, a message is sent
to the alert operator that it's time to get another disk drive
before this one fails.
NOTE:
The software defect map is written at block of the PV device.
This map is 22 blocks in size (AIX 3.1 version) and has enough
space to hold about 1400 defects. Hardware relocations are performed
only on WRITE operations where a READ request will return an I/O
error back to the requesting application.
top
of page
Compares text
files for differences
Example:
diff -wi filea fileb
-w ignores all spaces and tab characters
-i case insensitive
top
of page
Deletes entries
in the error log
Example:
errclear 0 (Truncates the errlog
to 0 bytes)
top
of page
Generates
an error report from entries in the error log
| Examples |
What
it does |
| errpt
-a|pg |
Produces
a detailed report for each entry in the error log |
| errpt
-aN hdisk1 |
Displays
an error log for ALL errors occurred on this drive. If
more than a few errors occur within a 24 hour period, execute
the CERTIFY process under DIAGNOSTICS to determine if a PV
is becoming marginal. |
| /etc/lpp/disagnostics/bin/run_ela |
Use
this script to DETERMINE or JUSTIFY hard file REPLACEMENT.
A message will be displayed on the CONSOLE device if a THRESHOLD
value has been reached in regards to the number of hard
file errors logged by the errpt utility. The following message
may be seen: HDISKx : ERROR LOG
ANALYSIS INDICATES A HARDWARE FAILURE. (x
represents the hdisk number) |
top
of page
Restarts the
system without checking the file systems with the fsck
command
top
of page
Halts the
system
top
of page
Finds files
with matching expressions.
Note: If the
following error message is generated
find: 0652-081 cannot change directory to </transfer/printers>:
file access permissions do not allow the specified action.
This
means that the user you are currently logged in as (even root)
doesn't have the authority to READ that directory.
| Examples |
What
it does |
| find
/ -name jan92.rpt -print |
Search
all file systems for any file named jan92.rpt |
| find
/ -size +1000k -exec ls -l {} \; -print |
Searches
all file systems to report back those files larger than 1
MB in size |
| find
/ -size 0 -print |
Find
all files of ZERO length |
| find
/ -type f -exec grep bananas {} \; -print |
Searches
all plain files to determine if the string 'bananas' is contained
within it |
| find
/usr/lpp/FINANCIALS -print | xargs chown roger.staff |
Changes
the ownership of all files under /usr/lpp/FINANACIALS to be
owned by user roger and have a group ownership of staff. |
| find
/ -user roger -print |
Find
all files owned by user roger |
| find
/ -nouser -print |
Displays
all unowned files in the system |
| find
/ -group staff -print |
Find
all files owned by group staff |
| find
/ -nogroup staff -print |
List
all files that belong to a non-existent group not found in
/etc/group |
| find
. -perm 600 -print | xargs chmod 666 |
Find
all the files that have READ/WRITE permissions set for the
owner of a file and change those permissions to READ/WRITE
for everybody. |
| find
/ -mtime +100 -print |
Search
all file systems for files that have not be modified in over
100 days. |
| find
. -mtime 0 -print |
List
all files in the current directory that have changed during
the current 24 hour period. |
| find
/ -name /transfer -prune -o -print |
List
the name of all files from the / (root) directory except for
the NFS file system named /transfer |
| find
. -name PERSONAL -prune -o -print |
List
the name of all files in or below the current directory, except
the directory named PERSONAL or files in that directory. |
| find
/ -fstype nfs -print |
List
the name of all the files that reside in an NFS file system |
| find
. -newer disk.log -print |
Display
all files that have been modified more recently than the file
named disk.log |
top
of page
Searches a
file for a pattern. Grep stands for Global Regular Expression
Printer
| Examples |
What
it does |
| grep
-i WhereIs * |
Search
all files in current directory to determine if the string
'WhereIs' is contained within it. The -i option ignores the
case of letters (WhereIs is same as whereis) |
| lsdev
-C|grep lp |
List
all configured printers |
| grep
[0-9][A-Z] *.doc |
List
any file that has a .doc suffix that contains a number (0-9)
followed by a capital letter (A-Z). |
| grep
[^0-5][A-Z] *.doc |
List
any file that has a .doc suffix that contains any number except
0 to 5 and is followed by a capital letter (A-Z) |
| grep
"^IBM" *.doc |
Displays
lines that BEGIN with the word IBM |
| grep
"IBM$" *.doc |
Displays
lines that END with the word IBM |
| grep
"^IBM is GREAT$" *.doc |
Displays
only those lines that consist of the phrase 'IBM IS GREAT' |
| grep
-v "^ *$" testfile > goodfile |
Removes
all the blank lines from the source file 'testfile' and redirects
the output to a new file named 'goodfile'. |
top
of page
Displays the
first 10 lines (default) of a file.
Example:
head -25 /tmp/phase2.out (Displays
the first 25 lines of the file /tmp/phase2.out.)
top
of page
Displays the
system identity of the user
| Examples |
What
it does |
| id |
uid=0(root)
gid=0(system) |
| id
-ru |
Displays
the UID of the current login process 0 |
top
of page
Display information
about previous logins stored in the /usr/adm/wtmp accounting file
| Examples |
What
it does |
| last
reboot|head -5 |
List
last 5 times systems has been rebooted |
| last
roger |
Display
times user roger has logged in/out of the system |
| last
tty0 |
Display
times users have logged in/out of port tty0 |
top
of page
Initiates
a new user session.
Example:
login -h rs6000 root
Login to the root account on a machine whose hostname is rs6000
top
of page
Terminates
all processes on the port your logged in on, including your login
shell. Note: exit will perform the
same action as logout.
Example:
logout (Logs you off the system. Login prompt will
reappear.)
top
of page
List contents
of the /etc/inittab file
Example:
lsitab -a
top
of page
List maximum
number of users that can be concurrently logged in
Example:
lslicense
Outputs: Maximum number of concurrent users: >32
top
of page
Sends a signal
to stop or suspend a process from running
Example:
kill -l (Lists valid
signals to use with the kill command.)
top
of page
Produces an
output file by inserting the line number of each line of an input
file at the beginning of each line
Example:
nl /etc/passwd > /tmp/user.list
top
of page
Execute a
command at a lower priority. Super-user may run commands with
a higher priority by using a negative number. Higher numbers mean
lower priorities (base priority is 10)
| Examples |
What
it does |
| nice
-n 15 make |
Run
the 'make' command at the low priority of 15 |
| nice
-10 /usr/bin/mview |
Run
the 'mview' application at a high priority of 10 |
top
of page
Convert EBCDIC
files to ASCII
| Examples |
What
it does |
| nvdmetoa
<AS400.dat >AIXver3.dat |
Converts
an EBCDIC file taken off an AS400 and converts to an ASCII
file for the RS/6000 |
| nvdmetoa
132 <AS400.txt >AIXver3.txt |
Converts
an EBCDIC file with a record length of 132 characters to an
ASCII file with 132 bytes per line PLUS 1 byte for the linefeed
character. |
top
of page
Dumps the
contents of a file in the requested format (ASCII,octal, hex,
or extended character set)
| Examples |
What
it does |
| od
-c /tmp/rc.net.out |
-c
displays bytes as ascii characters |
1)
od -cd
2) \<FUNCTION KEY>
3) \<SHIFT><FUNCTION KEY>
4) \<ALT><FUNCTION KEY> |
By
typing in this command, one may check the control codes being
generated by function keys. From the command line, you press
the '\' (backslash) character, then press a function key which
results in the escape sequence for that key to be displayed. |
Removes an
entry from the /etc/inittab file
Example:
rmitab ice (Removes the ice stanza
from the /etc/inittab file)
Stream edit
command to change text.
| Examples |
What
it does |
| cat
/tmp/mytest | sed -e "s/reports/report/" > /tmp/mytest |
All instances
of the string "reports" is replaced with the string
"report" for the file named /tmp/mytest |
| sed
-e 's/ *$//' < SOURCE_FILE > DESTINATION_FILE |
Removes
trailing blanks, not internal blanks, from each line in a
file |
| sed
'/total/d' /tmp/report > /tmp/report1 |
Delete
all lines that contains the word total |
| sed
'/^$/d' /tmp/report > /tmp/report1 |
Delete
all blank lines from file |
| sed
's/[ ]//g' /ibm/report > /tmp/report |
Delete
all tabs from file |
top
of page
Shutdown system
operations
| Examples |
What
it does |
| shutdown
+0 |
Shuts
down a system immediately. |
| shutdown
-Fr |
Shuts
down the system cleanly, followed by rebooting the system. |
| shutdown
-Fm |
Shuts
down the system into maintenance mode. When
using the 'm' option, make sure you are at the console, because
thats where control will be returned to. |
top
of page
Makes smaller
files from a large one. Each of the new files can be up to a specified
number of lines long. The smaller files are each named with the
input filename or a specified name, followed by an 'x' and an
increasing two letter sequence (xaa, xab, etc).
Example:
stopsrc -a
Gracefully shuts down all subsystems controlled by the SRC
- System Resource Controller.
top
of page
Removes symbol
table and other Extended Common Object File Format (XCOFF) data
from an executable image.
Example:
strip /usr/bin/uniplex
Reduces the storage overhead required by an executable file.
This translates to less real memory usage required to have program
run.
top
of page
Runs a sub-shell
with the effective user ID of the username passed in as a parameter
to this command (root if no parameter is passed). Type in
'exit', or 'logout' to return to previous user's session.
| Examples |
What
it does |
| su
roger |
Sets
up environment as if you had logged in as user roger WITHOUT
executing /etc/environment, $HOME/.profile or changing directories
to $HOME for user roger. |
| su
- root |
Initializes
the user environment from attributes set in the /etc/security/user
database and /etc/environment file, followed by executing
the $HOME/.profile and changing directories to $HOME. Basically
sets up the environment as if you had logged in as root. |
top
of page
Displays a
checksum for a file. Often used to validate if a file has been
corrupted by comparing the suspect file's checksum to that of
a known good file. Used to verify if a file has been corrupted
or a file transfer was sent/received properly.
Example:
sum /unix
Outputs: 13042 1253 /unix
top
of page
Displays the
last 10 lines (default) of a file.
Example:
tail /tmp/phase2.out
top
of page
Used to preserve
intermediate outputfrom within a pipeline to a file for later
processing or review
Example:
find . -cpio /dev/fd0 -print | tee /tmp/BACKUP.LOG
A list of the files backed up by the cpio command will be
saved by the tee utility in a file named /tmp/BACKUP.LOG
top
of page
| Examples |
What
it does |
| telinit
q |
Forces
the init process to re-read the /etc/inittab |
| telinit
1 |
Brings
the operating system into maintenance (single-user) mode.
Same as typing in init 1 |
top
of page
Displays the
elapsed time it took for a command to execute. Real time is amount
of time user waited for the process to execute. CPU time is amount
of time that the process actually used the cpu.
Example:
timex find /tmp -print|backup -ivqf/dev/null
top
of page
Translates
characters in a file. Handy for translating files from uppercase
(DOS files) to lowercase (UNIX files).
| Examples |
What
it does |
| tr
'~' '\012' </tmp/DOSFILE > /tmp/UNIXFILE |
Replace
the tilde as a DELIMITER character in file DOSFILE with a
NEWLINE character in file UNIXFILE. |
| tr
-d '\15' < file1 > file2 |
Remove
CR from file1 and creates a new file named file2 |
top
of page
Kernel debugging
to trace the events associated with the device your are monitoring.
| Examples |
What
it does |
| traceon |
turns
trace on |
| traceoff |
turns
trace off |
Shows path
location of the specified command
Example:
type basename
Outputs: basename is /usr/bin/basename
top
of page
Displays attributes
relating to hardware/software.
| Examples |
What
it does |
| uname
-a |
Displays
system name, operating system version, LAN network number,
type of hardware running and so on. |
| uname
-m |
XXYYYYYYMMSS
(machine ID) where...
- XX=Feature
of operating system. Always 00
- YYYYYY=CPU
ID. Value stored in ROM on processor board
- MM=Model
number. Set to 7th & 8th digits returned by lscfg
-v command
- SS=Submodel
number. Always 00
|
| uname
-rv |
-r=release,
-v=version. Results: 2 3
(Version 3 Release 2) |
| uname
-S `hostname` |
Since
the system name can be set in two places (hostname and uname
-S), just set them to the same string. |
top
of page
Lists summary
of current user activity
top
of page
Displays header
information about the source files required to build the executable
file your reviewing, timestamps as to when the source files where
compiled, their build level, and so on.
Example:
what /unix
top
of page
Displays a
short description of the function a command performs
Example:
whatis vmstat
Outputs: vmstat(1) - Reports virtual memory statistics.
top
of page
Shows path
location of the specified command
Example:
whereis motd
Outputs: motd: /etc/motd
top
of page
Displays information
about all users currently on local system. When you log in, the
login program writes a record in the /etc/utmp file. This record
includes your user name, date, time of login, and the login tty/pts
device. The who command checks this file to find out which
users are currently logged in, along with the hostname and display
terminal they are logged under.
| Examples |
What
it does |
| who
-b |
Displays
date system was last booted system boot Nov
17 13:58 |
| who
-r |
Displays
run-level of machine |
| who
-u |
Displays
information about users currently logged in. The line activity
field will EITHER have...
- a
dot (.) if there has been activity on the terminal within
the past minute OR
- the
number of hours/minutes since activity last occurred OR
- is
marked with 'old' if the line has been quiet for more
than 24 hours.
|
| who
-a /usr/adm/wtmp |
Displays
the name, terminal, and date users logged into the system |
| who
-u /etc/security/failedlogin |
Displays
the account, terminal and date that a failed login was attempted. |
| /usr/lib/acct/fwtmp
< /usr/adm/wtmp > /tmp/ACCT.INFO |
Creates
an ASCII version of the /usr/adm/wtmp file that can be read
by the system administrator |
Constructs
an argument list and executes a command
| Examples |
What
it does |
| find
/u/netinst -print | xargs chmod 500 |
Files
under /u/netinst will have permissions changed to 500 |
| find
/u/netinst -print | xargs chown netinst |
Files
under /u/netinst will have ownership changed to netinst |
| find
/u/netinst -print | xargs chgrp staff |
Files
under /u/netinst will have group changed to staff |
top
of page |
Business Info 