SYNCTEX(5) File Formats Manual SYNCTEX(5)
NAME
synctex — Synchronize TeXnology help file
DESCRIPTION
Synchronize TeXnology help file (synctexs) are text files that help in-
put/output synchronization during document preparation with the TeX
typesetting system.
BASICS
The structure of this file should not be considered public, in the sense
that no one should need to parse its contents, except the synctex com-
mand line utility, and the synctex_parser library which are both pub-
licly available. Unless it is absolutely not avoidable, access to the
contents of the synctex file should only be made through requests made
to the synctex command line utility.
STRUCTURE
The element structure of a synctex file is a list of text line records
as follows. ‘*’, ‘+’, and ‘?’ have their usual EBNF meanings: ‘*’ means
zero or more, ‘+’ means one or more, and ‘?’ means zero or one (i.e.,
optional).
<SyncTeX> ::= (The whole contents in 4 sections)
<Preamble>
<Content>
<Postamble>
<Post Scriptum>
Each section starts with the first occurrence of a sectioning line, and
ends with the next section, if any. In the following definitions, we do
not mention the section ending condition.
The preamble
<Preamble> ::=
"SyncTeX Version:" <Version Number> <EOL>
<Input Line>*
"Magnification:" <TeX magnification> <EOL>
"Unit:" <unit in scaled point> <EOL>
"X Offset:" <horizontal offset in scaled point> <EOL>
"Y Offset:" <vertical offset in scaled point> <EOL>
<Input Line> ::= "Input:" <tag> ":" <File Name> <EOL>
The content
<Content> ::=
<byte offset record>
"Content:" <EOL>
(<Form(k)>|<Input Line>)*
<sheet(1)>
(<Form(k)>|<Input Line>)*
<sheet(2)>
(<Form(k)>|<Input Line>)*
...
<sheet(N)>
(<Form(k)>|<Input Line>)*
<byte offset record> ::= "!" <byte offset> <end of record>
<sheet(n)> ::=
<byte offset record>
"{" <the integer n> <end of record>
<vbox section>|<hbox section>
<byte offset record>
"}" <the integer n> <end of record>
<Form> ::=
<byte offset record>
"<" <form tag> <end of record>
<vbox section>|<hbox section>
<byte offset record>
">" <end of record>
<form tag> ::= <integer>
Forms are available with pdfTeX. All the numbers are integers encoded
using the decimal representation with "C" locale. The <box content> de-
scribes what is inside a box. It is either a vertical or horizontal
box, with some records related to glue, kern or math nodes.
<box content> ::=
<vbox section>|<hbox section>
|<void vbox record>|<void hbox record>
|<current record>|<glue record>|<kern record>
|<math record>|<form ref record>|<Form>
<vbox section> ::=
"[" <link> ":" <point> ":" <size> <end of record>
<box content>*
"]" <end of record>
<hbox section> ::=
( <link> ":" <point> ":" <size> <end of record>
<box content>*
")" <end of record>
Void boxes:
<void vbox record> ::= "v" <link> ":" <point> ":" <size> <end of
record>
<void hbox record> ::= "h" <link> ":" <point> ":" <size> <end of
record>
<link> ::= <tag> "," <line>( "," <column>)?
<point> ::= <full point>|<compressed point>
<full point> ::= <integer> "," <integer>
<compressed point> ::= <integer> ",="
<line> ::= <integer>
<column> ::= <integer>
<size> ::= <Width> "," <Height> "," <Depth>
<Width> ::= <integer>
<Height> ::= <integer>
<Depth> ::= <integer>
The forthcoming records are basic one liners.
<current record> ::= "x" <link> ":" <point> <end of record>
<kern record> ::= "k" <link> ":" <point> ":" <Width> <end of
record>
<glue record> ::= "g" <link> ":" <point> <end of record>
<math record> ::= "$" <link> ":" <point> <end of record>
<form ref record> ::= "f" <form tag> ":" <point> <end of record>
The postamble
The postamble closes the file If there is no postamble, it means that
the typesetting process did not end correctly.
<Postamble>::=
<byte offset record>
"Count:" <Number of records> <EOL>
The post scriptum
The post scriptum contains material possibly added by 3rd parties. It
allows one to append some transformation (shift and magnify). Typi-
cally, one applies a dvi to pdf filter with offset options and magnifi-
cation, then he appends the same options to the synctex file, for exam-
ple
synctex update -o foo.pdf -m 0.486 -x 9472573sp -y 13.3dd source.dvi
<Post Scriptum>::=
<byte offset record>
"Post Scriptum:" <EOL>
"Magnification:" <number> <EOL> (Set additional
magnification)
"X Offset:" <dimension> <EOL> (Set horizontal offset)
"Y Offset:" <dimension> <EOL> (Set vertical offset)
This second information will override the offset and magnification pre-
viously available in the preamble section. All the numbers are encoded
using the decimal representation with "C" locale.
USAGE
The <current record> is used to compute the visible size of hbox's. The
byte offset is an implicit anchor to navigate the synctex file from
sheet to sheet. The second coordinate of a compressed point has been re-
placed by a "=" character which means that it is the second coordinate
of the last full point available above.
SEE ALSO
synctex(1) tex(1)
AUTHOR
The Synchronize TeXnology is essentially due to Jerome Laurens, with
useful suggestions by some well known actors of the TeX world. SyncTeX
is maintained as part of TeX Live.
HISTORY
This document has been updated on Sat Apr 22 09:57:20 UTC 2017 to in-
clude \pdfxform support.
Independent Aug 30, 2022 SYNCTEX(5)
Generated by dwww version 1.16 on Tue Dec 16 05:45:55 CET 2025.