--- name: "sd_path_lookup" section: "3" platform: "linux" package: "systemd-libs" version: "262.1-1" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/sd_path_lookup" --- # sd\_path\_lookup(3) Query well-known file system paths ## NAME sd\_path\_lookup, sd\_path\_lookup\_strv - Query well-known file system paths ## SYNOPSIS ``` #include ``` ``` enum { SD_PATH_TEMPORARY, SD_PATH_TEMPORARY_LARGE, SD_PATH_SYSTEM_BINARIES, SD_PATH_SYSTEM_INCLUDE, SD_PATH_SYSTEM_LIBRARY_PRIVATE, SD_PATH_SYSTEM_LIBRARY_ARCH, SD_PATH_SYSTEM_SHARED, SD_PATH_SYSTEM_CONFIGURATION_FACTORY, SD_PATH_SYSTEM_STATE_FACTORY, SD_PATH_SYSTEM_CONFIGURATION, SD_PATH_SYSTEM_SEARCH_CONFIGURATION, SD_PATH_SYSTEM_RUNTIME, SD_PATH_SYSTEM_RUNTIME_LOGS, SD_PATH_SYSTEM_STATE_PRIVATE, SD_PATH_SYSTEM_STATE_LOGS, SD_PATH_SYSTEM_STATE_CACHE, SD_PATH_SYSTEM_STATE_SPOOL, SD_PATH_USER_BINARIES, SD_PATH_USER_LIBRARY_PRIVATE, SD_PATH_USER_LIBRARY_ARCH, SD_PATH_USER_SHARED, SD_PATH_USER_CONFIGURATION, SD_PATH_USER_RUNTIME, SD_PATH_USER_STATE_PRIVATE, SD_PATH_USER_STATE_CACHE, SD_PATH_USER, SD_PATH_USER_DOCUMENTS, SD_PATH_USER_MUSIC, SD_PATH_USER_PICTURES, SD_PATH_USER_VIDEOS, SD_PATH_USER_DOWNLOAD, SD_PATH_USER_PUBLIC, SD_PATH_USER_TEMPLATES, SD_PATH_USER_DESKTOP, SD_PATH_USER_PROJECTS, SD_PATH_SEARCH_BINARIES, SD_PATH_SEARCH_BINARIES_DEFAULT, SD_PATH_SEARCH_LIBRARY_PRIVATE, SD_PATH_SEARCH_LIBRARY_ARCH, SD_PATH_SEARCH_SHARED, SD_PATH_SEARCH_CONFIGURATION_FACTORY, SD_PATH_SEARCH_STATE_FACTORY, SD_PATH_SEARCH_CONFIGURATION, SD_PATH_SYSTEMD_UTIL, SD_PATH_SYSTEMD_SYSTEM_UNIT, SD_PATH_SYSTEMD_SYSTEM_PRESET, SD_PATH_SYSTEMD_USER_UNIT, SD_PATH_SYSTEMD_USER_PRESET, SD_PATH_SYSTEMD_SYSTEM_CONF, SD_PATH_SYSTEMD_USER_CONF, SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT, SD_PATH_SYSTEMD_SEARCH_USER_UNIT, SD_PATH_SYSTEMD_SYSTEM_GENERATOR, SD_PATH_SYSTEMD_USER_GENERATOR, SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR, SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR, SD_PATH_SYSTEMD_SLEEP, SD_PATH_SYSTEMD_SHUTDOWN, SD_PATH_TMPFILES, SD_PATH_SYSUSERS, SD_PATH_SYSCTL, SD_PATH_BINFMT, SD_PATH_MODULES_LOAD, SD_PATH_CATALOG, SD_PATH_SYSTEMD_SEARCH_NETWORK, SD_PATH_SYSTEMD_SYSTEM_ENVIRONMENT_GENERATOR, SD_PATH_SYSTEMD_USER_ENVIRONMENT_GENERATOR, SD_PATH_SYSTEMD_SEARCH_SYSTEM_ENVIRONMENT_GENERATOR, SD_PATH_SYSTEMD_SEARCH_USER_ENVIRONMENT_GENERATOR, }; ``` **int sd\_path\_lookup(uint64\_t** *type***, const char \****suffix***, char \*\****paths***);** **int sd\_path\_lookup\_strv(uint64\_t** *type***, const char \****suffix***, char \*\*\****paths***);** ## DESCRIPTION **sd\_path\_lookup()** and **sd\_bus\_path\_lookup\_strv()** return a single path or set of file system paths specified by the argument *type*. In case of **sd\_path\_lookup()** a single **NUL**-terminated string is returned. When *type* specifies a set of paths, they are concatenated using ":" as a separator (as is traditionally done for e.g. *$PATH* or *$LD\_LIBRARY\_PATH*). In case of **sd\_path\_lookup\_strv()** a **NULL**-terminated array of strings is returned (strv). If suffix *suffix* is given, it is concatenated to each of the paths after a slash ("/"). All returned paths are absolute. For paths which refer to user directories, the relevant XDG standard is followed, with support for environment variables like *$XDG\_DOCUMENTS\_DIR*, *$XDG\_DESKTOP\_DIR*, ..., and explicit configuration in /etc/xdg/user-dirs.conf or ${XDG\_CONFIG\_HOME}/user-dirs.dirs. See **XDG Base Directory Specification**\[1\] for details. [**systemd-path**(1)](/systemd-path/1.md) is a wrapper around **sd\_path\_lookup()** and allows the same set of paths to be queried. ## RETURN VALUE On success, **sd\_path\_lookup()** and **sd\_path\_lookup\_strv()** return a non-negative integer. On failure, a negative errno-style error number is returned by either function. The returned string or string array (strv) must be [**free**(3)](/free/3.md)'d by the caller. ### Errors Returned errors may indicate the following problems: **-EOPNOTSUPP** Unknown identifier *type*. Added in version 246. **-EINVAL** Output argument is **NULL**. Added in version 246. **-ENXIO** Query failed because of an undefined environment variable (e.g. for **SD\_PATH\_USER\_RUNTIME** when *$XDG\_RUNTIME\_DIR* is not defined). Added in version 246. **-ENOMEM** Memory allocation failed. Added in version 246. ## EXAMPLES ### Look up the location of ~/Documents ``` /* SPDX-License-Identifier: MIT-0 */ #include #include #include int main(void) { int r; char *t; r = sd_path_lookup(SD_PATH_USER_DOCUMENTS, NULL, &t); if (r < 0) return EXIT_FAILURE; printf("~/Documents: %s\n", t); free(t); return EXIT_SUCCESS; } ``` Note that the default answer of $HOME/Documents may be overridden by user-dirs.conf or *$XDG\_DOCUMENTS\_DIR*. ## NOTES Functions described here are available as a shared library, which can be compiled against and linked to with the **libsystemd** [**pkg-config**(1)](/pkg-config/1.md) file. The code described here uses [**getenv**(3)](/getenv/3.md), which is declared to be not multi-thread-safe. This means that the code calling the functions described here must not call [**setenv**(3)](/setenv/3.md) from a parallel thread. It is recommended to only do calls to **setenv()** from an early phase of the program when no other threads have been started. ## HISTORY **sd\_path\_lookup()** and **sd\_path\_lookup\_strv()** were added in version 246. ## SEE ALSO [**systemd**(1)](/systemd/1.md), [**sd-path**(3)](/sd-path/3.md), [**systemd-path**(1)](/systemd-path/1.md) ## NOTES - 1\. XDG Base Directory Specification https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html