The device and environment files also contain much material which any site will need, so care must be taken when editing the files. Important changes may be made to the global portions of these files as part of any IRAF release. To facilitate future updates, it is wise where possible to isolate any local changes or additions so that they may simply be extracted and copied into the new (distributed) version of the file in a future update.
The zzsetenv.def file contains a number of environment definitions. Many of these define IRAF logical directories and should be left alone. Only those definitions in the header area of the file should need to be edited to customize the file for a site. It is the default editor, default device, etc. definitions in this file which are most likely to require modification for a site.
If the name of a default device is modified, the named device must also have
an entry in the termcap file (terminals and printers used for text
hardcopy) or the graphcap file (graphics terminals and image displays
and graphics hardcopy printers) in iraf/dev.
There must also be an editor.ed file in dev for the
default editor; edt, emacs, and vi are examples of
currently supported editors.
Sample values of those variables most likely to require modification for a site are shown below.
set editor = "vi" set printer = "lpr" set stdplot = "lpr" set stdimage = "imt512"For example, you may wish to change the default editor to "emacs", the default printer to "lw5", or the default image display to "imt800". Note that the values of terminal and stdgraph, which also appear in the zzsetenv.def file, have little meaning except for debugging processes run standalone, as the values of the environment variables are reset automatically by stty at login time. The issues of interfacing new graphics and image display devices are discussed further in §5.
Examples of things one might want to change in the template login.cl
are the commented out environment definitions, the commented out CL
parameter assignments, the foreign task definitions making up the default
user package, and the list of packages to be loaded at startup
time. For example, if there are host tasks or local packages which
should be part of the default IRAF operating environment at your site,
the template login.cl is the place to make the necessary changes.
dev$tapecap. This replaces the "devices" file used in earlier versions
of IRAF. The tapecap file describes each local magtape device and controls all
i/o to the device, as well as device allocation.
In V2.10 IRAF there was one tapecap file per IRAF installation and all
client nodes sharing the same central version installation required device
entries in the global tapecap file. In V2.11 this scheme has been
generalized to allow each host to have its own private tapecap file, with a
fallback to the generic tapecap file if no host-specific file is found.
The system will look first for a configuration file called
tapecap.node where node is the hostname of the server the
tapecap file describes. If that is not found the default tapecap
file will be used. In this way a separate tapecap file can be created for
each node allowing a name such as 'mta' to always refer to the first tape
on that machine regardless of whether it varies in type from node to node.
Alternatively, sites may wish to maintain only a single tapecap file with
generic device names describing the different types of tape drives
available on the local network. In either case the devices.hlp
file described in the next section should be edited to document for the
user the tape devices available at your site.
The tapecap files included in the distributed system include some generic device entries such as "mtxb1" (Exabyte unit 1, Sun ST driver), "mthp2" (HP7880 9 track drive, unit 2), and so on which you may be able to use as-is to access your local magtape devices. The exact list of available device types depend on the platform in question. Most likely you will want to add some device aliases, and you may need to prepare custom device entries for local devices. There must be an entry in the tapecap file for a magtape device in order to be able to access the device from within IRAF. All magtape device names must begin with the two-letter prefix "mt".
tapecap file is text data base file (similar to the
termcap and graphcap files) describing the capabilities and
device names associated with a particular tape device on the system. For
information on the format of the file see the termcap(5) man page. A listing
of all recognized fields is given in the program comments for the tape
driver in iraf$unix/os/zfiomt.c (more on this later). In general, creating
a new tapecap entry for a device is a matter of finding a similar entry in
the distributed file, and either using that directly if the device names are
correct, or simply modifying it slightly to change device names so it will
be appropriate for a drive on a different SCSI unit or using a different host
driver. On occasion, other tapecap parameters will need to be added to
correct for specific behavior that affects appending new data and tape
positioning.A tapecap entry for a device is usually divided into three different sections: a high-level entry giving the name of the drive as known to IRAF, a mid-level section defining the host device names associated with the drive, and a low-level generic section describing capabilities associated with all instances of a particular type of drive (DAT, Exabyte, 9-track, etc.). The starting point for the tapecap entry is whatever iraf name was used to access the drive. This is usually something like 'mta', 'mtb', etc but can be any valid name beginning with an 'mt' prefix and which defines all the needed parameters. When searching for a particular tapecap parameter the first occurrence of that parameter in the entry is used by the system, and a complete tapecap description is composed of all the entries which are linked by the :tc continuation fields.
As an example consider a typical entry for a DAT drive on unit 0 known to a Solaris/IRAF system as 'mta', the high-level entry would look like:
mta|Generic DAT entry, unit 0| :tc=mtst0.solaris.dat:Here we define the iraf name (which must begin with an 'mt' prefix) along with any aliases delimited by the '|'. The :tc field continues the tapecap at the next entry named "mtst0.solaris.dat":
mtsd0|mtst0.solaris.dat|DAT drive on Solaris:\\
:al=0 0bn 0cb 0cn 0hb 0hn 0lb 0ln 0mb 0mn 0u 0ubn \\
0b 0c 0cbn 0h 0hbn 0l 0lbn 0m 0mbn 0n 0ub 0un:\\
:dv=0bn:lk=0:tc=solaris-dat:
This entry is primarily used to specify the host device names associated
with the drive. The :al (aliases) field is a list of all device
aliases in the UNIX /dev or /dev/rmt directories associated with this
device. This is needed so the tape allocation task can properly change the
permissions and ownership on each device name which accesses that tape
drive. The :dv (device) field is the no-rewind device name and
is the device file actually opened for tape I/O; this must be a no-rewind
device since IRAF will maintain the tape position automatically. The actual
device name typically depends on the density of the tape, whether
compression is used etc. The :lk is used to build the name of a "lok
file" that is created in the /tmp directory of the machine hosting the drive
that will be used to maintain the tape status and position information; this
value should be unique for each drive on the machine to avoid conflicts.
When configuring a new tapecap entry, all one usually needs change is the
iraf device name in the first section and the host device names in the :dv,
:al and :lk fields of this entry. Finally this section continues the entry
with a :tc field saying to branch to the "solaris-dat" generic entry:
solaris-dat|sdat-60m|Sun/Solaris DAT drive:\\
:dt=Archive Python 4mm Helical Scan tape drive:tt=DG-60M:\\
:ts#1274378:bs#0:mr#0:or#65536:fb#10:fs#127000:mf:fe#2000:
The low-level entry here is where parameters relating to all drives of a
particular type using a particular host tape driver are maintained, e.g.
the record sized used for tape I/O, positioning capabilities, filemark sizes,
etc. These will rarely need to be changed from the distributed entries unless
you are using a new tape driver or a different model tape drive, or a
type of tape cartridge with a capacity different than that given ("tz").
See the section below for a full list of the tapecap parameters and their
meanings.
For a more complicated example let's consider how to add an entry for an Exabyte 8505 drive given an existing entry for an Exabyte 8200 device. We can ignore for now the low-level entry found in the distributed tapecap and concentrate on what fields actually need changing in this case. We begin with the high-level entry defining the iraf names, we will need one name for the drive in each of three modes (8200 mode, 8500 mode, and 8500 mode w/ compression):
mta|Exabyte 8200, Unit 0| :tc=mtst0.solaris.exb8200: mtb|mtblo|Exabyte 8505, Unit 0| :tc=mtst0.exb8505-lo: mtbhi|Exabyte 8505, Unit 0| :tc=mtst0.exb8505-hi: mtbc|Exabyte 8505, Unit 0| :tc=mtst0.exb8505-c:The new iraf names are therefore mtb (8200 mode), mtbhi (8500 mode), and mtbc (8500 + compression). These all link to the second level entry where we make use of the existing EXB8200 entry:
mtsee0|mtst0.solaris.exb8200|Exabyte 8200 drive on Solaris:\\
:al=0 0bn 0cb 0cn 0hb 0hn 0lb 0ln 0mb 0mn 0u 0ubn \\
0b 0c 0cbn 0h 0hbn 0l 0lbn 0m 0mbn 0n 0ub 0un:\\
:dv=0bn:lk=0:tc=solaris-exb8200:
mtsee0lo|mtst0.exb8505-lo|:dv=0lbn:tc=mtsee0:
mtsee0hi|mtst0.exb8505-hi|:dv=0mbn:fs#48000:ts#5000000:tc=mtsee0:
mtsee0hic|mtst0.exb8505-c|:dv=0cbn:fs#48000:ts#5000000:tc=mtsee0:
Note that the names we just created link to the one-line entries below the
standard EXB 8200 entry 'mtst0.solaris.exb8200' (the mtb entry could
just as legally have linked to this entry right away). Since all we need to
change is the :dv field (because we're opening the same drive, but by
using a different name the host system accesses it in the appropriate mode)
we can simply make a new entry point, change the :dv field and then link to
the existing entry where all the rest of the parameters will be the same.
In this case we've also reset the :fs and :ts fields to override
the values in the low-level Exabyte description since these have also changed
for the new model drive. If we wished to modify this entry for a drive on
e.g. unit 2 all we would need to do is modify the various :dv, :al, and :lk
fields so the device names are correct, and change the name of the tapecap
entry points so we avoid any confusion later on.
When configuring a new tapecap and encounter problems it is useful to turn on status output so you get a better idea of where the tape is positioned and what's going on, to do this use the :so field as follows:
cl> set tapecap = ":so=/dev/tty"Alternatively, the :so can be specified on the command line, e.g.
cl> rewind "mta[:so=/dev/tty]"Any other tapecap parameters can be specified in the same way. The quotes around the tape name are required if any special characters such as '=' are included in the device name string. Status output like this can also be directed to an Xtapemon server running either locally or remotely, see the xtapemon man page for details. Help with configuring new tapecap entries is available from IRAF site support.
mta|Generic DAT entry, unit 0| :se:ow:tc=mtst0.solaris.dat:would add the ":se:ow" fields (discussed below) to only the mta device.
Boolean tapecap parameters may be negated if you are linking to an existing entry which already defines a particular field. For example, in
mta|Generic DAT entry, unit 0| :se@:tc=mtst0.solaris.dat:the '@' character would negate the :se field regardless of whether it is defined elsewhere in the entry.
One of the most common problems encountered is that only odd-numbered images on a tape are readable by the drive. The solution to this is usually to add a se to the tapecap to tell the driver that the tape will position past the EOT in a read. Another common problem is with appending new data to an existing tape, this sometimes requires the addition of a ow field to tell the driver to backspace and overwrite the EOT when appending. A re is sometimes needed if there is a problem sensing the EOT when reading all images from a tape, this tell the driver that a read at EOT returns an ERR.
The parameter fb may be specified for a device to define the "optimum" FITS blocking factor for the device. Unless the user explicitly specifies the blocking factor, this is the value that the V2.11 wfits task will use when writing FITS files to a tape. Note that for cartridge devices a FITS blocking factor of 22 is used for some devices; at first this may seem non-standard FITS, but it is perfectly legal, since for a fixed block size device the FITS blocking factor serves only to determine how the program buffers the data (for a fixed block device you get exactly the same tape regardless of the logical blocking factor). For non-FITS device access the magtape system defines an optimum record size which is used to do things like buffer data for cartridge tape devices to allow streaming.
Some devices, e.g. most Exabyte drives, are slow to switch between read and skip mode, and for files smaller than a certain size, when skipping forward to the next file, it will be faster to read the remainder of the file than to close the file and do a file skip forward. The fe parameter is provided for such devices, to define the "file equivalent" in kilobytes of file data, which can be read in the time that it takes to complete a short file positioning operation and resume reading. Use of this device parameter in a tape scanning application such as rfits can make a factor of 5-10 difference in the time required to execute a tape scan of a tape containing many small files.
On a device such as most cartridge tape devices where backspacing is not permitted or does not work reliably it may be necessary to set the nf parameter to tell the driver to rewind and space forward when backspacing to a file.
Lastly, when configuring a new low-level generic entry for the device it is sometimes necessary to change the various size parameters for the drive. These include:
bs device block size (0 if variable) fb default FITS blocking factor (recsize=fb*2880) fe time to FSF equivalent in file Kb mr maximum record size or optimum record size fs approximate filemark size (bytes) ts tape capacity (Mb) dn densityAll but the last three fields are used either by the driver or a task when reading or writing a tape, the :fs, ts and :dn fields are used by tape monitoring tasks such as xtapemon to compute the approximate amount of tape used and do not affect tape operation. For devices which are capable of variable block size I/O (i.e. almost anything but a cartridge tape) it is best to leave the bs field at zero. The maximum and optimum record sizes, the mr and or fields, are usually determined by the host tape driver used. Values for these can either be found in the host driver man page or it's system include file.
cl> help devicesor just
cl> devicesin the CL will format and output the contents of this file. It is the IRAF name of the device, as given in files such as termcap, graphcap, and tapecap, which should appear in this help file followed by a brief description of the device, see the distributed file as an example. Starting with V2.10 this file in no longer used to configure tape devices, it is informational only.
DD. This consists of three fields: the device name,
e.g. "node!device", the template for the temporary spoolfile, and the UNIX
command to be used to dispose of the file to the printer. On most UNIX
systems it is not necessary to make use of the node name and IRAF networking
to access a remote device since UNIX lpr already provides this
capability, however it might still be useful if the desired device does not
have a local lpr entry for some reason. Printer devices named in this
file may be used for text hardcopy output such as you get from the LPRINT
task, graphics hardcopy devices are configured by editing the
graphcap file discussed in the next section.As an example, assume we have a printer known to the sun as 'lw5', the termcap entry would look something like:
lw5|lp5| :tc=sapple5:
sapple5|sapple|Apple laser writer NT on Orion:\\
:co#80:li#66:os:pt:ta^I:\\
:DD=lpnode!apple,/tmp/asfXXXXXX,!{ lpr -Plw5 $F; rm $F; }:
To then create an entry for a new device named 'lw16' simply copy this
entry and change the '5' to '16' in the device and termcap entry
names, and especially in the lpr command of the DD string.
The $F denotes the name
of the file to be printed, specifically the temp file created so it should
be removed to avoid filling up the disk. Note that the DD string
can contain any valid unix command to print a file to a specific device, we
use various local print commands, Enscript, etc.
If you have a local terminal which has no entry in the IRAF termcap file,
you probably already have an entry in the UNIX termcap file. Simply copy it
into the IRAF file; both systems use the same termcap database format and
terminal device capabilities. However, if the terminal in question is a
graphics terminal with a device entry in the graphcap file, you should
add a `:gd' capability to the termcap entry. If the graphcap entry
has a different name from the termcap entry, make it `:gd=gname'.
lp5|lw5| :tc=uapl5:
uapl5|UNIX generic interface to 300dpi printer on Orion:\\
:xs#0.269:ys#0.210:ar#0.781:\\
:DD=apl,tmp$sgk,!{ sgidispatch sgi2uapl $F -l$(XO) -w$(XW) \\
-b$(YO) -h$(YW) -p$(PW) | lpr -Plw5; rm $F; }&:tc=sgi_apl:
where the device is known to the system as lw5 or lp5. The
entry is very similar in form to the termcap entry discussed above,
and changing it for a new device is primarily a matter of changing the
device names. The exception however is in the DD string: here instead
of a simple print command we invoke an SGI translator via the
sgidispatch command (in this case the sgi2uapl translator) which
is used to the convert the graphics kernel metacode to PostScript for the
final printing. The arguments to the sgi2uapl translator are the
device resolution and offset parameters obtained from the sgi_apl
entry linked by the :tc field at the end of the graphcap entry. The output
from the translator is piped to a printer and the temp file is removed.
If we wish to convert this entry for a different type of printer, aside from the changing the name in the graphcap entries and the print command, the DD string may have to be changed to call a new SGI translator with the appropriate arguments, and the final :tc field would have to link to a new entry appropriate for that device. In V2.11 the following SGI translators are available:
sgi2uapl.c - PostScript for LaserWriters and PS plotters sgi2ueps.c - Encapsulated PostScript, PS-Adobe-3.0, EPSF-3.0 sgi2uhpgl.c - HP Graphics Language for HP 7550A and others sgi2uimp.c - Impress language for Imagen printers sgi2uqms.c - QMS Vector Graphics (Talaris Lasergrafix) sgi2uhplj.c - HP Printer Command Language (LaserJet Series) sgi2uptx.c - Printronix plotterIn addition, Versatec plotters are supported (no SGI translator needed).
stdimage
devices for the system. These are basically just frame buffer configurations
describing the size of the image display being used (whether it's an actual
frame buffer such as an IIS mode 70 or a display server such as XImtool or
SAOimage). A typical entry for a 512x512 frame buffer looks like:
imt1|imt512|imtool|Imtool display server:\\
:cn#1:LC:BS@:z0#1:zr#200:DD=node!imtool,,512,512:tc=iism70:
Here the :cn field is the configuration number and the frame buffer
size is given in the DD field. For display servers such as XImtool
the configuration number is passed to the server which then uses that as an
index to the imtoolrc file (normally installed by the system as a link
to dev$imtoolrc) it uses to determine the frame buffer size to be used.
When adding a new frame buffer you need to be sure the :cn field is unique
and the size in the graphcap file agrees with the size in the imtoolrc file
for that config, both files must be edited for the new size to be
recognized correctly. Note that SAOimage has a limit of 64 possible frame
buffers that will be recognized, XImtool and SAOtng recognize up to 128
possible configurations.
cl> help gio$doc/gio.hlp fi+ | lprintThis will print the document on the default IRAF printer device which will be the default printer for your machine or the one named by your UNIX
PRINTER environment variable (use the "device=" hidden parameter to
specify a different device). Alternatively, to view the file on the
terminal,
cl> phelp gio$doc/gio.hlp fi+The help pages for the IRAF tasks showcap and stty should also be reviewed as these utilities are useful for generating new graphcap entries. The i/o logging feature of stty is useful for determining exactly what characters your graphcap device entry is generating. The gdevices task is useful for printing summary information about the available graphics devices.
hosts,
irafhosts, and uhosts) used by the IRAF network interface.
IRAF networking is used to access remote image displays, printers, magtape
devices, files, images, etc. via the network. Nodes do not necessarily have
to have the same architecture, or even run the same operating system, so
long as they can run IRAF.To enable IRAF networking for a UNIX/IRAF system, all that is necessary is to edit the "hosts" file. Make an entry for each logical node, in the format
nodename [ aliases ] ":" irafks.e-pathnamefollowing the examples given in the hosts file supplied with the distribution (which is the NOAO/Tucson hosts file). Note that there may be multiple logical entries for a single physical node.
The "uhosts" file is not used by UNIX/IRAF systems hence does not need to be modified (it used by VMS/IRAF). The "irafhosts" file is the template file used to create user .irafhosts files. It does not have to be modified, although you can do so if you wish to change the default parameter values given in the file.
To enable IRAF networking on a particular IRAF host, the host OS hostname (i.e. the output of the unix hostname command) must appear as a primary name or alias somewhere in the IRAF hosts table. On systems where this is the fully qualified host name (FQHN) the node name may exceed a limit 16-character limit on a node name so at least one alias should include a truncated version of the FQHN, the entire FQHN should appear on the right side of the ':' in the irafks.e pathname. During process startup, the IRAF VOS looks for the system name for the current host and automatically disables networking if this name is not found. Hence IRAF networking is automatically disabled when the distributed system is first installed - unless you are unlucky enough to have installed the system on a host with the same name as one of the nodes in the NOAO host table. Note that it may be best to simply delete the NOAO host table entries since any duplicate with a local host entry will will cause the IRAF "cd" command to fail and may have other consequences.
Once IRAF networking is configured, the following command may be typed in the CL to verify that all is well:
cl> netstatusThis will print the host table and state the name of the local host. Read the output carefully to see if any problems are reported.
Alternatively users can set up a private hosts table by copying the system version and making any additions. To then make use of this define a CL environment variable irafhnt which is the path to the private hosts file. For example,
cl> copy dev$hosts home$myhosts # make private copy cl> edit home$myhosts # edit any changes cl> reset irafhnt = home$myhosts # reset hosts table to be used cl> flpr 0 # reinitialize system to use itYou can also define a UNIX irafhnt variable in the same way prior to logging into the CL to accomplish the same thing.
For IRAF networking to be of any use, it is necessary that IRAF be installed on at least two systems. In that case either system can serve as the server for an IRAF client (IRAF program) running on the other node. It is not necessary to have a separate copy of IRAF on each node, i.e., a single copy of IRAF may be NFS mounted on all nodes (you will need to run the IRAF install script on each client node). If it is not possible to install IRAF on a node for some reason (either directly or using NFS) it is possible to manage by installing only enough of IRAF to run the IRAF kernel server. Contact IRAF site support if you need to configure things in this manner.
UNIX IRAF systems currently support only TCP/IP based networking. Networking between any heterogeneous collection of systems is possible provided they support TCP/IP based networking (virtually all UNIX-based systems do). The situation with networking between UNIX and VMS systems is more complex. Contact the IRAF project for further information on networking between UNIX and VMS systems.
Once IRAF networking is enabled, objects resident on the server node may be accessed from within IRAF merely by specifying the node name in the object name, with a "node!" prefix. For example, if foo is a network node,
cl> page foo!hlib$motd cl> allocate foo!mta cl> devstatus foo!mtaIn a network of "trusted hosts" the network connection will be made automatically, without a password prompt using the rsh protocol. A password prompt will be generated if the user does not have permission to access the remote node with UNIX commands such as rsh. Hosts are made "trusted" in a network by listing them in the system
/etc/hosts.equiv
file, most often when rsh fails it's because this file hasn't been configured,
usually for security reasons. User's can configure a .rhosts file in
their UNIX login directories (see the rhosts(5) man page) to make the hosts
trusted for their account and bypass the passwd prompt. Each user also has
a .irafhosts file in their UNIX login directory which can be used to exercise
more control over how the system connect to remote hosts. See the discussion
of IRAF networking in the IRAF Version 2.10 Revisions Summary (in
iraf$doc/v210revs.ms), or in the V2.10 system notes file, for a more in-depth
discussion of how IRAF networking works.To keep track of where files are in a distributed file system, IRAF uses network pathnames. A network pathname is a name such as "foo!/tmp3/images/m51.pix", i.e., a host or IRAF filename with the node name prepended. The network pathname allows an IRAF process running on any node to access an object regardless of where it is located on the network.
Inefficiencies can result when image pixel files are stored on disks which are cross-mounted using NFS. The typical problem arises when imdir (the pixel file storage directory) is set to a path such as "/data/iraf/user/", where /data is a NFS mounted directory. Since NFS is transparent to applications like IRAF, IRAF thinks that /data is a local disk and the network pathname for a pixel file will be something like "foo!/data/iraf" where "foo" is the hostname of the machine on which the file is written. If the image is then accessed from a different network node the image data will be accessed via an IRAF networking connection to node "foo", followed by an NFS connection to the node on which the disk is physically mounted, causing the data to traverse the network twice, slowing access and unnecessarily loading the network.
cl> set imdir = "server!/data/iraf/user/"This also has the advantage of avoiding NFS for pixel file access - NFS is fine for small files but can load the server excessively when used to access bulk image data.
Alternatively, one can set imdir to a value such as "HDR$pixels/", or disable IRAF networking for disk file access. In both cases NFS will be used for image file access.
If the system has been installed according to the instructions given in the
installation guide the login directory for the IRAF account will be
iraf/local. This directory contains both a .login file
defining the environment for the IRAF account, and a number of other "dot"
files used to setup the IRAF system manager's working environment.
Most site managers will probably want to customize these files according to their personal preferences. In doing this please use caution to avoid losing environment definitions, etc., which are essential to the correct operation of IRAF, including IRAF software development and maintainence.
The default login.cl file supplied in the IRAF login directory uses machine
independent pathnames and should work as-is (no need to do a mkiraf -
in fact mkiraf has safeguards against inadvertent use within the IRAF
directories and may not work in iraf/local). It may be necessary to edit
the .login file to modify the way the environment variable IRAFARCH
is defined. This variable, required for software development but optional
for merely using IRAF, must be set to the name of the desired machine
architecture, e.g., sparc, vax, rs6000, ddec, etc. If it is set to the name
of an architecture for which there are no binaries, e.g., generic, the CL
may not run, so be careful. The alias setarch, defined in the iraf
account .login, is convenient for setting the desired architecture for IRAF
execution and software development.
IRAFARCH in the user environment is not required unless the user
will be doing any IRAF based software development (including IMFORT).
Programmers doing IRAF software development may wish to source
hlib$irafuser.csh in their .login file as well.