NAME

       sd_path_lookup, sd_path_lookup_strv - Query well-known file system paths

SYNOPSIS

       #include <systemd/sd-path.h>

       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_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_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) 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)'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 <stdio.h>
           #include <stdlib.h>
           #include <systemd/sd-path.h>

           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) file.

       The code described here uses getenv(3), which is declared to be not multi-thread-safe.
       This means that the code calling the functions described here must not call setenv(3) 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-path(1)

NOTES

        1. XDG Base Directory Specification
           https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html