.Dd March 6, 2021
.Dt SERDI 1
.Os Serd 0.30.11
.Sh NAME
.Nm serdi
.Nd read and write RDF syntax
.Sh SYNOPSIS
.Nm serdi
.Op Fl abefhlqtvx
.Op Fl I Ar base
.Op Fl c Ar prefix
.Op Fl i Ar syntax
.Op Fl k Ar bytes
.Op Fl o Ar syntax
.Op Fl p Ar prefix
.Op Fl r Ar root
.Op Fl s Ar string
.Op Fl w Ar filename
.Ar input ...
.Sh DESCRIPTION
.Nm
is a fast command-line utility for streaming and processing RDF data.
It reads one or more RDF documents and writes the data again,
possibly transformed and/or in a different syntax.
By default,
the input syntax is guessed from the file extension,
and output is written in NTriples or NQuads.
.Pp
.Nm
can be used to check for syntax errors,
convert from one syntax to another,
pretty-print documents,
or transform URIs and blank node IDs.
.Pp
The options are as follows:
.Pp
.Bl -tag -compact -width 3n
.It Fl I Ar base
Input base URI.
Relative URI references in the input will be resolved against this.
When the input is a file,
the URI of the file is automatically used as the base URI.
This option can be used to override that,
or to provide a base URI for input from stdin or a string.
.Pp
.It Fl a
Write ASCII output.
If this is enabled, all non-ASCII characters will be escaped, even if the output syntax allows them to be written in UTF-8.
.Pp
.It Fl b
Bulk output writing.
If this is enabled, output will be written a page at a time, rather than a byte at a time.
.Pp
.It Fl c Ar prefix
Chop
.Ar prefix
from matching blank node IDs.
This is the inverse of
.Fl p .
.Pp
.It Fl e
Eat input one character at a time, rather than a page at a time which is the default.
This is useful when reading from a pipe since output will be generated immediately as input arrives, rather than waiting until an entire page of input has arrived.
With this option serdi uses one page less memory, but will likely be significantly slower.
.Pp
.It Fl f
Keep full URIs in input (don't qualify with namespace prefixes or make URIs relative).
.Pp
.It Fl h
Print the command line options.
.Pp
.It Fl i Ar syntax
Read input as
.Ar syntax .
Case is ignored, valid values are:
.Dq NQuads ,
.Dq NTriples ,
.Dq TriG ,
and
.Dq Turtle .
.Pp
.It Fl k Ar bytes
Parser stack size.
For performance and security reasons, parsing is performed with a fixed-size stack.
By default, the stack is 4096 bytes, which should be sufficient for most data.
If some data has very deep nesting or very large literal values,
it may exceed the default amount of space,
and this option can be used to increase it and allow the document to be parsed successfully.
.Pp
.It Fl l
Lax (non-strict) parsing.
If this is enabled, recoverable syntax errors will print a warning, but parsing will proceed starting at the next statement if possible.
Note that data may be lost when using this option.
.Pp
.It Fl o Ar syntax
Write output as
.Ar syntax .
Case is ignored, valid values are:
.Dq empty ,
.Dq NQuads ,
.Dq NTriples ,
.Dq TriG ,
and
.Dq Turtle .
When
.Dq empty
is given, output is suppressed, so only errors will be printed.
.Pp
.It Fl p Ar prefix
Add
.Ar prefix
to blank node IDs.
This can be used to avoid clashes between blank node IDs in input documents.
.Pp
.It Fl q
Suppress all output except data.
.Pp
.It Fl r Ar root
Keep relative URIs within a
.Ar root
URI.
This will avoid creating any relative URI references with leading path segments like
.Dq ../
that enter a parent of
.Ar root .
.Pp
.It Fl s Ar string
Parse
.Ar string
as input.
.Pp
.It Fl t
Write terser output without newlines.
.Pp
.It Fl v
Display version information and exit.
.Pp
.It Fl w Ar filename
Write output to the given
.Ar filename
instead of stdout.
.Pp
.It Fl x
Support parsing variable nodes.
Variables can be written in SPARQL style, for example
.Dq ?var
or
.Dq $var .
.El
.Sh EXIT STATUS
.Nm
exits with a status of 0, or non-zero if an error occured.
.Sh EXAMPLES
To pretty-print a document:
.Pp
.Dl $ serdi -o turtle file.ttl > out.ttl
.Pp
To print any errors:
.Pp
.Dl $ serdi file.ttl > /dev/null
.Sh SEE ALSO
.Bl -item -compact
.It
.Lk http://drobilla.net/software/serd/
.It
.Lk http://gitlab.com/drobilla/serd/
.El
.Sh STANDARDS
.Bl -item
.It
.Rs
.%A W3C
.%T RDF 1.1 NQuads
.%D February 2014
.Re
.Lk https://www.w3.org/TR/n-quads/
.It
.Rs
.%A W3C
.%D February 2014
.%T RDF 1.1 NTriples
.Re
.Lk https://www.w3.org/TR/n-triples/
.It
.Rs
.%A W3C
.%T RDF 1.1 TriG
.%D February 2014
.Re
.Lk https://www.w3.org/TR/trig/
.It
.Rs
.%A W3C
.%D February 2014
.%T RDF 1.1 Turtle
.Re
.Lk https://www.w3.org/TR/turtle/
.El
.Sh AUTHORS
.Nm
is a part of serd, by
.An David Robillard
.Mt d@drobilla.net .