Streamline and document exit codes

[backup-script.git] / README.md

diff --git a/README.md b/README.md
index 81201368630d718253fe0d65b28e83720e4d95d0..f816c05c6d0766b0384a6150fd4463be966562c0 100644 (file)
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@ Options:
 - `-p`, `--progress`: Show progress, see rsync(1).
 - `-n`, `--dry-run`: Test run only, don't copy any data.
 
-When no *system* is given, all defined systems are used.
+When no *system* is given, all defined systems are backed up.
 
 ### backup-script-wrapper
 
@@ -38,15 +38,17 @@ Options:
 
 ## Configuration
 
-All defauklt configuration variables are read from `/etc/backup-script.conf`,
+All default configuration variables are read from `/etc/backup-script.conf` or
 from `/etc/backup-script.d/backup-script.conf` (deprecated). The individual
 systems are configured using individual files in `/etc/backup-script.d/`, one
-for each system to backup (files ending in `*.sh` are skipped).
+for each system to backup (files ending in `*.sh` are skipped, as well as
+files named `backup-script.conf`). Please avoid spaces and other "special"
+characters!
 
 Variables in `backup-script.conf` must be prefixed with `default_` to define
 default values for all systems.
 
-All default can be overwritten in individual system configuration files.
+All defaults can be overwritten in individual system configuration files.
 
 For example:
 
@@ -55,7 +57,7 @@ For example:
 - `/etc/backups-script.d/clientXY.example.com`: configuration for host 2
 
 
-## Configuration Variable
+## Configuration Variables
 
 ### system
 
@@ -113,11 +115,22 @@ Default: 0 (off; use ssh).
 
 Number of generations to keep. Default: 0 (none).
 
-On a *btrfs* target file systems (see `target` variable), this script can
-generate generations using *btrfs snapshots*: the script creates a new snapshot
-named with the timestamp for each generation inside of the system directory
+On a suitable target file systems (see `target` variable), this script can
+generate generations using snapshots: the script creates a new snapshot
+named with the time stamp for each generation inside of the system directory
 inside of the target directory.
 
+Supported file systems are:
+
+ * *btrfs*:
+   All generations are btrfs subvolumes and named after the date and time.
+ * *ZFS*:
+   All generations are ZFS file systems. Latest generation is named `current`,
+   elders are links to the ZFS snapshot directories.
+
+The latest snapshot is always reachable using a symlink named `latest`
+inside the system directory.
+
 ### [default_]job_pre_exec
 
 Optional script to execute before `rsync` starts. Default: none.
@@ -138,3 +151,14 @@ definition files are automatically mapped to the new backup-script variables:
 * source -> source_root
 * pre_exec -> job_pre_exec
 * post_exec -> job_post_exec
+
+
+## Exit codes
+
+- 1: Unspecific Error!
+- 2: Usage information has been shown.
+- 3: Can't read system definition
+- 4: PID-file exists!
+- 5: Pre-exec command failed!
+- 6: There have been systems with errors!
+- 9: Aborted (CTRL-C)!