If you get this error, you probably have one of the following things wrong:

• You've forgotten the slash and semicolon in the find command. Use find command like this:

  # find /tmp -mtime +5 -type f -exec rm {} \;

• If you get this error from crontab, then you should add an extra slash to the slash and semicolon. Use the find command like this:

  0 2 * * * find /tmp -mtime +5 -type f -exec rm {} \\;

If you wish to put AIX files on a CD, you *COULD* use Windows. But, Windows files have certain restrictions on file length and permissions. Also, Windows can't handle files that begin with a dot, like ".toc", which is a very important file if you wish to burn installable filesets on a CD.

How do you solve this problem?

• Put all files you wish to store on a CD in a separate directory, like: /tmp/cd
• Create an ISO file of this directory. You'll need mkisofs to accomplish this. This is part of the AIX Toolbox for Linux. You can find it in /opt/freeware/bin.

  # mkisofs -o /path/to/file.iso -r /tmp/cd

• This will create a file called file.iso. Make sure you have enough storage space.
• Transfer this file to a PC with a CD-writer in it.
• Burn this ISO file to CD using Easy CD Creator or Nero.
• The CD will be usable in any AIX CD-ROM drive.

Let's say you wish to calculate with dates within a Korn Shell script, for example "current date minus 7 days". How do you do it? There's a tiny C program that can do this for you, called ctimed. You can download it here: ctimed.tar.

Executable ctimed uses the UNIX Epoch time to calculate. UNIX counts the number of seconds passed since Januari 1, 1970, 00:00.

So, how many seconds have passed since 1970?

# current=`./ctimed now`

# let week=7*24*60*60

# ./ctimed $aweekago

If you wish to clone a system with a mksysb, then you can do so, but you do not want your cloned system to come up with the same TCP/IP information. Just issue rmtcpip before creating the mksysb, and you have a perfect image for cloning to another system. Be sure to issue this command at a terminal, as you will lose your network connection!

There are times that you would like to create some "load" on the system. A very, very easy way of keeping a processor very busy is:

# yes > /dev/null

To monitor all lpars within 1 frame, use:

# topas -C

To quickly show you the processor speed, cpu type, amount of memory and other system information, type:

# lsconf

To use a DVD-RAM for writing and reading like a file system, use the following commands. This will work only at AIX 5.2 and above:

• Put a DVD-RAM into the drive

  # udfcreate -d /dev/cd0

• Mount the DVD-RAM:

  # mount -V udfs /dev/cd0 /mnt

  If you get an error, ensure /etc/vfs contains this line (and retry the mount command after validating):

  udfs 34 /sbin/helpers/udfmnthelp

You can use a DVD-RAM to create a system backup. To do so, enter:

# smitty mkdvd

To retrieve a list of all recent commands:

# history -100