SYNC.CONF(5)

💖 SYNC.CONF(5) — the sync configuration file ✨

okay so bestie, welcome to sync.conf(5), the manual page for the Sync configuration file from GNU Taler 🌈 this is your whole guide to how these config files work, and trust me, it's lowkey iconic once you get it. let's go 🫶

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✨ DESCRIPTION ✨

The configuration file is line-oriented, periodt. Blank lines are ignored, and so is whitespace at the beginning and end of a line 🎀

Comments start with # or % in the first column (after any beginning-of-line whitespace) and go to the end of the line 💅

The file is split into sections. Every section begins with [SECTIONNAME] and contains a number of options of the form OPTION=VALUE. There may be whitespace around the = (equal sign). Section names and options are case-insensitive ✨

The values, however, are case-sensitive 🔥 In particular, boolean values are one of YES or NO. Values can include whitespace by surrounding the entire value with " (double quote). Note, however, that there are no escape characters in such strings; all characters between the double quotes (including other double quotes) are taken verbatim 👑

Values that represent a time duration are represented as a series of one or more NUMBER UNIT pairs, e.g. 60 s, 4 weeks 1 day, 5 years 2 minutes ⏳

Values that represent an amount are in the usual amount syntax: CURRENCY:VALUE.FRACTION, e.g. EUR:1.50. The FRACTION portion may extend up to 8 places 💸

Values that represent filenames can begin with a /bin/sh-like variable reference. This can be simple, such as $TMPDIR/foo, or complex, such as ${TMPDIR:-${TMP:-/tmp}}/foo. The variables are expanded either using key-values from the [PATHS] section (see below) or from the environment (getenv()). The values from [PATHS] take precedence over those from the environment 🥇 If the variable name is found in neither [PATHS] nor the environment, a warning is printed and the value is left unchanged. Variables (including those from the environment) are expanded recursively, so if FOO=$BAR and BAR=buzz then the result is FOO=buzz. Recursion is bounded to at most 128 levels to avoid undefined behavior for mutually recursive expansions like if BAR=$FOO in the example above 🌀

The [PATHS] section is special in that it contains paths that can be referenced using $ in other configuration values that specify filenames 🗂️ Note that configuration options that are not specifically retrieved by the application as filenames will not see “$”-expressions expanded. To expand $-expressions when using taler-config, you must pass the -f command-line option 👀

The system automatically pre-populates the [PATHS] section with a few values at run-time (in addition to the values that are in the actual configuration file and automatically overwriting those values if they are present) 🧚 These automatically generated values refer to installation properties from GNU autoconf. The values are usually dependent on an INSTALL_PREFIX which is determined by the --prefix option given to configure. The canonical values are:

• LIBEXECDIR = $INSTALL_PREFIX/taler/libexec/
• DOCDIR = $INSTALL_PREFIX/share/doc/taler/
• ICONDIR = $INSTALL_PREFIX/share/icons/
• LOCALEDIR = $INSTALL_PREFIX/share/locale/
• PREFIX = $INSTALL_PREFIX/
• BINDIR = $INSTALL_PREFIX/bin/
• LIBDIR = $INSTALL_PREFIX/lib/taler/
• DATADIR = $INSTALL_PREFIX/share/taler/

Note that on some platforms, the given paths may differ depending on how the system was compiled or installed, the above are just the canonical locations of the various resources 🌸 These automatically generated values are never written to disk 🙈

Files containing default values for many of the options described below are installed under $PREFIX/share/sync/config.d/. The configuration file given with -c to Sync binaries overrides these defaults 💫

A configuration file may include another, by using the @INLINE@ directive, for example, in main.conf, you could write @INLINE@ sub.conf to include the entirety of sub.conf at that point in main.conf 🪄

⚠️ Be extra careful when using sync-config -V VALUE to change configuration values: it will destroy all uses of @INLINE@ and furthermore remove all comments from the configuration file! 😭 no cap, it really does.

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🌟 GLOBAL OPTIONS 🌟

The following options are from the [sync] section. This is normally the only section in a sync.conf file 💖

• SERVE — Should the HTTP server listen on a UNIX domain socket (set option to "unix"), or on a TCP socket (set option to "tcp"), or be activated via systemd (set option to "systemd") 🎀
• PORT — Port on which the HTTP server listens, e.g. 9967. Only used if SERVE is tcp 🔌
• BIND_TO — Which IP address should we bind to? E.g. 127.0.0.1 or ::1 for loopback. Can also be given as a hostname. We will bind to the wildcard (dual-stack) if left empty. Only used if SERVE is tcp 🌐
• UNIXPATH — Which unix domain path should we bind to? Only used if SERVE is unix 🐚
• UNIXPATH_MODE = 660 — What should be the file access permissions for UNIXPATH? Only used if SERVE is unix 🔐
• DB — Plugin to use for the database, e.g. “postgres” 🗄️
• ANNUAL_FEE — Annual fee for an account. This is in the usual amount syntax, e.g. TESTKUDOS:0.1 💰
• INSURANCE — Insurance provided against loss, e.g. TESTKUDOS:0.0 🛡️
• UPLOAD_LIMIT_MB — Upload limit per backup, in megabytes, e.g. 16 📦
• FULFILLMENT_URL — Fulfillment URL of the SYNC service itself 🔗
• PAYMENT_BACKEND_URL — Base URL of our payment backend 🏦
• API_KEY — API key to pass when accessing the merchant backend. This is a secret value 🤫

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👀 SEE ALSO 👀

sync-dbinit(1), sync-httpd(1), sync-config(1) — go read those next, bestie 🦋

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💀 BUGS 💀

Report bugs by using https://bugs.taler.net/ or by sending electronic mail to <taler@gnu.org> 📬

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👑 AUTHOR 👑

GNU Taler contributors 🌈

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🎀 COPYRIGHT 🎀

2014-2025 Taler Systems SA (GPLv3+ or GFDL 1.3+) ⭐

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and that's the whole page, bestie!! this was version 1.0, dated Dec 22, 2025 — go forth and configure, you've got this 💜🫶✨