LGWAM(1) User Commands LGWAM(1)NAMElgwam - Logiweb Abstract Machine
SYNOPSISlgwam command [file arg1 ... argn]
DESCRIPTION
In normal use, the lgwam command is installed in /usr/bin/lgwam and is
used as the first line of Logiweb scripts. The first line of such
scripts typically read
#!/usr/bin/lgwam script
The Logiweb compiler lgc(1) generates such scripts. The format of
scripts is described in SCRIPT FORMAT below.
OPTIONS
The lgwam command may take the following forms:
lgwam script FILE ARG1 ... ARGn
Execute the given file as a Logiweb program. Pass the command
line arguments to the program with FILE as ARG0. For the format
of FILE see SCRIPT FORMAT below.
lgwam test
Execute basic built in testsuite.
lgwam testrun FILE
Load the Logiweb page referenced in FILE and all pages refer‐
enced transitively from that page. Then execute an extended
testsuite. The extended testsuite first executes the basic test‐
suite. Then the extended testsuite looks for pages named 'base',
'check', 'Peano', and 'test'. If one or more of these are found,
the extended testsuite executes a number of associated tests.
The FILE must be a Logiweb script, c.f. SCRIPT FORMAT below.
lgwam dry
Do dry run: initialize memory and exit.
lgwam { -h | help | --help }
Print help message
lgwam { -v | version | --version }
Print version and license information.
lgwam { pages | --pages }
List built in pages.
SCRIPT FORMAT
A Logiweb script file consists of lines of text. Blank lines and lines
starting with a hash mark (#) are ignored. Lines can be ended by arbi‐
trary sequences of CR and LF characters.
A script may look thus:
#!/usr/bin/lgwam script
string
015F43BE4A17DAD915936B7A773154A80946AEC82EFBEECDA4A7D7B80806
hello
execute
foo=bar
magicword=xyzzy
The first line starts with a hash mark so it is ignored.
The first proper line (the second line) indicates the format of the
rest of the script. The 'string' format is the only format which is not
deprecated, so the first proper line always says 'string'.
The second proper line contains the reference of a Logiweb page
expressed in mixed endian hexadecimal, c.f. REFERENCES below.
The third proper line indicates the name of the program ('hello' in
this case).
The fourth proper line indicates the aspect defining the program. The
lgc compiler always sets the aspect to 'execute'.
All remaining lines define script options which are passed to the pro‐
gram.
When lgwam executes a Logiweb script, it first loads the referenced
page and all its transitively referenced pages. It does so using the
LGW_PATH environment variable described under ENVIRONMENT below.
Then lgwam looks up the given aspect of the given name on the refer‐
enced page where both aspect and name are treated as strings. The base
page which comes with the distribution defines the 'execute' aspect of
'hello' such that the resulting program prints 'Hello World'.
Then lgwam invokes the given aspect of the given name in the way
described on the base page. See the base page for further information.
ENVIRONMENT
Whenever lgwam needs to load a page, it locates the page using the
LGW_PATH environment variable. If that variable is not set, it defaults
to
$HOME/.logiweb/logiweb/:/rack.lgr
The value of LGW_PATH must be a list of locations separated by semi‐
colons. The default path above contains only one location and, thus, no
semicolons.
To load a referenced page, lgwam tries each location in turn. For each
location, lgwam replaces the rightmost colon character by the reference
of the page expressed in mixed endian hexadecimal, c.f. REFERENCES
below. Then lgwam reads the file at the resulting path, if any. The
file must be a rack file, c.f. logiweb(5).
REFERENCES
The Logiweb reference of a Logiweb page is a sequence of around 30
bytes which identifies the page uniquely. References are often
expressed in mixed endian hexadecimal.
In mixed endian hexadecimal, each byte is represented by two hexadeci‐
mal digits with the most significant digit first. Bytes are given in
network order. Capital letters are used for the hex digits A to F.
AUTHOR
Klaus Grue, http://logiweb.eu/
SEE ALSOlgc(1), lgc(5), lgc.conf(5), logiweb(5)Logiweb JULY 2009 LGWAM(1)
