elk/doc/man/elk.1

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.pl 11i \" US letter format
.TH ELK 1 "15 January 1991"
.UC 4
.SH NAME
elk, scheme-elk \- extensible Scheme interpreter
.SH SYNOPSIS
.B elk
[
.B \-l \f2file\fP
] [
.B \-h \f2KBytes\fP
] [
.B \-p \f2load-path\fP
] [
.B \-g
] [
.B \-i
] [
.B \-v \f2type\fP
] [[
.B \-\^\-
] \f2args\fP]
.LP
.BR elk .\|.\|.
.SH DESCRIPTION
.I Elk
(Extension Language Kit) is a Scheme implementation designed
as a general extension language for applications
written in C or C++.
Normally,
.I Elk
is linked with the application it serves, but a stand-alone version
of the Scheme interpreter is installed as well (usually under
the name
.BR elk ).
This interpreter, together with the standard Scheme toplevel,
.I Elk
can be used as an ordinary, stand-alone implementation of the
Scheme language.
.LP
When called without the
.B \-l
option,
.I Elk
loads the standard \*(lqtoplevel\*(rq to start an interactive session.
When called with
.BR "\-l \f2file\fP" ,
the contents of the specified file is loaded instead.
If a `\-' is given as a filename argument,
.I Elk
loads from standard input.
.LP
The option
.B \-p \f2load-path\fP
can be used to override the standard \f2load-path\fP.
The argument is a colon-separated list of directories.
If this option is not present and the environment variable
ELK_LOADPATH is defined, the value of this variable is used
to initialize the \f2load-path\fP.
The value of ELK_LOADPATH has the same format as the argument
to the
.B -p
option.
.LP
The
.B \-h \f2KBytes\fP
option is used to specify a non-standard heap size.
The default heap size is 512 KBytes.
.LP
If the option
.B \-i
is specified, symbols are mapped to lower case.
Normally,
.I Elk
is case-sensitive.
.LP
The
.B \-g
option causes the interpreter to run the garbage collector each
time memory is allocated on the heap.
This is useful for writers of extensions who want to test the
garbage collect behavior of an extension.
Running
.I Elk
with the
.B \-g
option is likely to reveal GC-related bugs in extensions (such as not
properly protected local objects), as it triggers a garbage collection
each time an object is allocated on the Scheme heap.
A dot is written to standard output each time a garbage collection is
performed when
.B \-g
has been specified.
.LP
When called with one or more
.B \-v \f2type\fP
(``verbose'') options, the interpreter prints additional
informational messages to standard output, depending on the value
of the \f2type\fP argument.
If \f2type\fP is \f2load\fP, the linker command and options are
printed each time an object file is loaded; if \f2type\fP is
\f2init\fP, the names of extension initialization
and finalization functions are printed as they are called.
.LP
The remaining
.I args
are put into a list of strings, and the Scheme variable
.B command-line-args
is bound to this list in the global environment.
If arguments could be interpreted as options, `\-\^-\' can be
used to indicate the end of the options.
.SH FILES
.nf
$TMPDIR/ldXXXXXX Temporary files
.fi
.SH AUTHOR
Oliver Laumann