OpenVMS Undocumented Features
This is the most complete collection of undocumented features we can find for OpenVMS. Some of these have been around since the time when it was called VMS while others are more current and have been added to OpenVMS V8.n. These features:
- Are NOT documented (if they were, they wouldn't belong here)
- Are NOT supported by PARSEC Group or HP
- Are NOT guaranteed to work
- May NOT exist in all versions of OpenVMS; past, present and future
- Are subject to change, removal, enhancement or being documented at the whim of OpenVMS engineering
- May be fun to know the next time you play OpenVMS trivial pursuit
- May help you get your job done easier and faster
- May help you impress your boss with your knowledge of the obscure
MCR Command
The MCR command has been used by most system managers for many years; yet it is not documented.
- Comes from RSX compatibility mode (for those who remember that far back)
- Stands for Monitor Console Routine
- Frequently used as a short-cut to run images in SYS$SYSTEM
- Can pass a single command line to the application like foreign commands
$ mcr sysgen show wsmax
Parameter Name Current Default Min. Max. Unit Dynamic
-------------- ------- ------- ------- ------- ---- -------
WSMAX 262144 8192 1024 134217728 Pagelets
internal value 16384 512 64 8388608 Pages
Setting line width for the DIFFERENCES command
The /LINE_WIDTH qualifier to the DIFFERENCES command controls the width of the output generated. This can be especially helpful when sending the output to a file that will be printed.
$ differences copy.com
************
File $22$DKA300:[WILLIAMS]COPY.COM;9
25 $! write sys$output "match ''count' found on fid ''fid', file ''fl'"
26 $ rename 'fl' [.multi] /log
27 $ goto top
******
File $22$DKA300:[WILLIAMS]COPY.COM;8
25 $ write sys$output "match ''count' found on fid ''fid', file ''fl'"
26 $! rename 'fl' [.multi] /log
27 $ goto top
************
Number of difference sections found: 1
Number of difference records found: 2
DIFFERENCES /IGNORE=()/MERGED=1-
$22$DKA300:[WILLIAMS]COPY.COM;9-
$22$DKA300:[WILLIAMS]COPY.COM;8
$ differences copy.com/line=40
************
File $22$DKA300:[WILLIAMS]COPY.COM;9
25 $! write sys$output "match ''cou
26 $ rename 'fl' [.multi] /log
27 $ goto top
******
File $22$DKA300:[WILLIAMS]COPY.COM;8
25 $ write sys$output "match ''coun
26 $! rename 'fl' [.multi] /log
27 $ goto top
************
Number of difference sections found: 1
Number of difference records found: 2
DIFFERENCES /IGNORE=()/WIDTH=40-
/MERGED=1-
$22$DKA300:[WILLIAMS]COPY.COM;9-
$22$DKA300:[WILLIAMS]COPY.COM;8
SYS$ETC directory of unsupported tools
The SYS$ETC directory contains unsupported tools. Some of these tools include built-in help. Use of these tools should be limited to non-production systems. Misuse of these tools can cause the lose of all data on a disk.
$ directory/column=1 sys$etc:
Directory SYS$COMMON:[SYSHLP.UNSUPPORTED]
CDDVD$COMPARE.EXE;1
CDDVD$COPY.EXE;1
CDDVD$DEVICE_TEST.COM;1
CDDVD$INFO.EXE;1
CDDVD$TESTPATT.EXE;1
CDDVD$TOOLS.CLD;1
CHECK_SECTIONS.COM;1
FC$CP.EXE;1
FIBRE_SCAN.EXE;1
MSA_UTIL.EXE;1
RF35_T392F_DEC_ALPHA.EXE;1
RF36_V427P_DEC_ALPHA.EXE;1
RF73_T392F_DEC_ALPHA.EXE;1
RF74_V427P_DEC_ALPHA.EXE;1
RF_VERS.EXE;1
RZ26L_442D_DEC.FUP;1
RZ28P4_442C_DEC.FUP;1
RZ28_442D_DEC2104.FUP;1
RZTOOLS_ALPHA.EXE;1
SCSI_INFO.EXE;1
SCSI_MODE.EXE;1
SCSI_PR_UTIL.EXE;1
T4_V34_KIT.EXE;1
T4_V34_KIT.TXT;1
VEVAMON.EXE;1
Total of 25 files.
The Love Editor
Define a foreign command called "make" pointing to the TECO editor.
For OpenVMS VAX
$ make :== $teco32 make
For OpenVMS Alpha
$ make :== $teco32_tv make
For OpenVMS I64
$ make :== $teco32_tv_av make
Then tell TECO to make love.
$ make love
Not war?
*
Please enjoy these features at your own risk. If you are aware of other features in OpenVMS which are currently undocumented, you may use our inquiry form to inform us. We may then add it to our list.