LAM-HELPFILE(5)

🌸 lam-helpfile — LAM help message file 🌸

okay bestie, so this is the manual page for lam-helpfile (it lives in section 5, "LAM FILE FORMATS", iykyk) and it's literally the glow-up guide for LAM's error messages. let's get into it 💖

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✨ DESCRIPTION ✨

so lam-helpfile is the file that holds all the detailed error messages and the lil suggestions on how to fix common problems. like, in a ton of places all over LAM, when something goes wrong, LAM peeks at this help file to show you a detailed message about what the error actually was and — when it can — suggestions on how to fix it. no cap. it's got a lot of the same info as the LAM FAQ (especially the parts about getting LAM up and running 🚀).

at present, these LAM tools use this help file (and it's expected that more will use it in future releases — if you've got suggestions for spots where more detailed error messages would be helpful, please let us know 🫶):

• hboot
• lamboot
• lamexec
• lamhalt
• lamnodes
• lamwipe
• mpicc (hcc)
• mpiCC (hcp)
• mpif77 (hf77)
• mpirun
• recon
• tkill
• tping

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🦋 STRUCTURE AND SYNTAX 🦋

the help file is just multiple blocks of help text, separated by single line delimiters. the delimiter lines look like this:

-*-programname:topicname-*-

where programname is the general name of the program (or group of programs) that this help message applies to, and topicname is the specific topic that this message applies to.

the special keyword ALL can be used for either the programname or the topicname in some cases; this is usually a "wildcard" value where little specific information is available. slay 💅

inside the block of the message, any lines that begin with a # are treated as comments — they don't get printed out. so go off, annotate, nobody will see it 🙈

three special escape sequences can be used within the help message:

• %N — where N is a number from 1 to the number of arguments that the help message is invoked with. the "%N" string gets replaced with the value of the Nth argument from the argument list. the arguments are passed from the LAM binaries themselves; they cannot be edited. the comments in the default LAM help file explain how many arguments each message is invoked with, and what each argument is.
• %perror — shows the result of the Unix perror(3) function.
• %terror — shows the result of the LAM terror() function, which is essentially a wrapper around the Unix perror(3) function.

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💜 LOCATION OF HELP FILE 💜

the exact location of the help file is configurable. this lets system administrators and/or users customize the help file for their particular environment. iconic, honestly.

when LAM attempts to print an error message from the help file, it looks for the help file in the following locations (in order):

• $HOME/lam-helpfile
• $HOME/lam-7.1.4-helpfile
• $HOME/etc/lam-helpfile
• $HOME/etc/lam-7.1.4-helpfile
• $LAMHELPDIR/lam-helpfile
• $LAMHELPDIR/lam-7.1.4-helpfile
• $LAMHOME/etc/lam-helpfile
• $LAMHOME/etc/lam-7.1.4-helpfile
• $TROLLIUSHOME/etc/lam-helpfile
• $TROLLIUSHOME/etc/lam-7.1.4-helpfile
• $SYSCONFDIR/lam-helpfile
• $SYSCONFDIR/lam-7.1.4-helpfile

note the variable $LAMHELPDIR; this variable can be set according to platform — for example, to provide operating system-specific information, or information specific to particular groups of machines, etc. it can also be set to provide help messages in different languages 🌈 (multilingual queen behaviour, fr fr).

$SYSCONFIDIR is typically $prefix/etc, where $prefix is the location to where LAM was installed; it was the option supplied to ./configure when LAM was built (or /usr/local/lam-7.1.4, by default). however, note that the value of $SYSCONFDIR can be overridden when LAM is configured with the --sysconfdir switch. 👑

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🎀 EXAMPLES 🎀

here's an example customization of the help for the hboot and lamboot programs, for when the user supplies a host file name that is not found:

-*-boot:open-hostfile-*-
%1 could not open the hostfile "%2" for the following reason:

            %perror
Things to check:

            - ensure that the file exists
              try "ls -l %2"
            - ensure that you have read permissions on the file
              try "cat %2"

You may not need to specify a host file at all; the system
administrators have defined the all of Beowulf cluster host names in
the LAM default host name list.  If you wish to use all of the Beowulf
nodes, simply execute:

            %1 -v

If you have any problems with LAM, please send mail to:

            lam-admin@your.domain.com

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🍓 FILES 🍓

• $LAMHOME/etc/lam-7.1.4-helpfile — default LAM help file

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💖 SEE ALSO 💖

hboot(1), lamboot(1), lamexec(1), lamhalt(1), lamnodes(1), lamwipe(1), mpicc(1), mpiCC(1), mpif77(1), mpirun(1), recon(1), tkill(1), tping(1), perror(3)

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and that's the whole vibe check, bestie — go forth and read your error messages, they're actually trying to help you 🫶✨

okay so this one's from LAM 7.1.4, dated July, 2007 — vintage but she still ate, and that's the whole manual page. periodt. 💅🌟