diff --git a/bin/bashbot_env.inc.sh b/bin/bashbot_env.inc.sh
index 72109be..4d93c46 100644
--- a/bin/bashbot_env.inc.sh
+++ b/bin/bashbot_env.inc.sh
@@ -13,7 +13,7 @@
 #        AUTHOR: KayM (gnadelwartz), kay@rrr.de
 #       CREATED: 18.12.2020 12:27
 #
-#### $$VERSION$$ v1.20-3-g232a16b
+#### $$VERSION$$ v1.21-dev-2-gde31231
 #===============================================================================
 
 ############
@@ -52,9 +52,10 @@ fi
 # shellcheck disable=SC1090
 source "${BASHBOT_HOME}/bashbot.sh" source "$1"
 
-# overwrite bot FILE regex to BASHBOT_ETC
+# overwrite bot FILE regex to BASHBOT_VAR
 # change this to the location you want to allow file uploads from
-FILE_REGEX="${BASHBOT_ETC%/bin*}/.*"
+UPLOADDIR="${BASHBOT_VAR%/bin*}"
+FILE_REGEX="${UPLOADDIR}/.*"
 
 # get and check ADMIN and NAME
 BOT_ADMIN="$(getConfigKey "botadmin")"
diff --git a/doc/3_advanced.md b/doc/3_advanced.md
index 7507f49..ef1e8db 100644
--- a/doc/3_advanced.md
+++ b/doc/3_advanced.md
@@ -106,7 +106,7 @@ echo -e "Your Message: ${test}\nbye!"
 #### message formatting and keyboards
 
 The output of the script will be processed by 'send_messages', so you can not only send text, but also keyboards, files, locations and more.
-Each newline in the output will start an new message to the userr. To have line breaks in your message you must insert ' mynewlinestartshere ' or '\n' instead.
+Each newline in the output will start an new message to the user. To have line breaks in your message you must insert ' mynewlinestartshere ' or '\n' instead.
 
 To open up a keyboard in an interactive script, print out the keyboard layout in the following way:
 ```bash
@@ -114,8 +114,11 @@ echo "Text that will appear in chat? mykeyboardstartshere [ \"Yep, sure\" , \"No
 ```
 Same goes for files:
 ```bash
-echo "Text that will appear in chat? myfilelocationstartshere /home/user/doge.jpg"
+echo "Text that will appear in chat? myfilelocationstartshere /home/user/dog.jpg"
 ```
+*Note*: Use an _absolute path name_ (starting with `/`), a relative path name is relative to `data-bot-bash/upload`!
+See [send_file documentation](6_reference.md#send_file) for more information.
+	
 And buttons:
 ```bash
 echo "Text that will appear in chat. mybtextstartshere Click me myburlstartshere https://dealz.rrr.de"
@@ -299,5 +302,5 @@ Note: If you disable automatic retry, se above, you disable also connection prob
 #### [Prev Getting started](2_usage.md)
 #### [Next Expert Use](4_expert.md)
 
-#### $$VERSION$$ v1.20-0-g2ab00a2
+#### $$VERSION$$ v1.21-dev-2-gde31231
 
diff --git a/doc/6_reference.md b/doc/6_reference.md
index c453f1d..9f18f72 100644
--- a/doc/6_reference.md
+++ b/doc/6_reference.md
@@ -114,20 +114,29 @@ The main use case for send_message is to process the output of interactive chats
 
 
 ##### send_file
-send_file allows you to send different type's of files, e.g. photos, stickers, audio, media, etc. [see more](https://core.telegram.org/bots/api#sending-files)
+send_file allows you to send different type's of files, e.g. photos, stickers, audio, media, etc. [see more](https://core.telegram.org/bots/api#sending-files).
+It's recommended to use the _absolute path name_ (starting with `/`). A relative path is threated as relative to `data-bot-bash/upload` as default UPLOADDIR.
 
-- file names must not contain ".."
-- file names must not start with "."
-- file names not starting with "/" are relative to $TMPDIR, e.g. ./data-bot-bash
-- absolute filenames must match $FILE_REGEX
-- FILE_REGEX is a regular expression, not shell globbing, test you rexexes: http://www.softlion.com/webTools/RegExpTest/
+For security reasons the following restrictions apply:
+
+- absolute path name must match the shell _regex_ FILE_REGEX (not file glob!)
+- path must not start with "." and not contain ".."
 
 *usage:* send_file "${CHAT[ID]}" "file" "caption"
 
 *example:*
 ```bash
-send_file "${CHAT[ID]}" "/home/user/doge.jpg" "Lool"
-send_file "${CHAT[ID]}" "https://www.domain,com/something.gif" "Something"
+# recommended absolute path
+send_file "${CHAT[ID]}" "/home/user/dog.jpg" "My Dog"
+
+# relative to default dir: data-bot-bash/upload/dog.jpg
+send_file "${CHAT[ID]}" "dog.jpg" "My Dog"
+
+# change to personal dir
+UPLOADDIR="/home/user/myuploaddir"
+
+# relative to changed dir: /home/user/myuploaddir/dog.jpg
+send_file "${CHAT[ID]}" "dog.jpg" "My Dog"
 ```
 
 ##### send_album
@@ -1145,5 +1154,5 @@ The name of your bot is available as bash variable "$ME", there is no need to ca
 #### [Prev Best Practice](5_practice.md)
 #### [Next Notes for Developers](7_develop.md)
 
-#### $$VERSION$$ v1.20-0-g2ab00a2
+#### $$VERSION$$ v1.21-dev-2-gde31231