now uses 'script' to provide a scrollback buffer at reattaching. Otherwise all screen output while not attached gets lost

session

@@ -8,8 +8,9 @@ typeset -A config
 config=(
     [socket_dir]="/tmp/"
     [socket_base]="session-$UID"
-    [shell]="/bin/bash"
+    [log_session]="yes"
-    [redraw]="winch"
+    [scrollback]="50"
+    [detach_char]=""
 )
 # Source from configuration file if available
 if [ -f "$CONFIG_FILE" ]; then
@@ -23,18 +24,19 @@ if [ -f "$CONFIG_FILE" ]; then
   done < $CONFIG_FILE
 fi
 
-## Set some variables
+# Set some variables
 SOCKET_PREFIX="${config[socket_dir]}/${config[socket_base]}-"
 SOCKET_SUFFIX=".socket"
+LOG_SUFFIX=".log"
 
 # Exit codes
 EXIT_SUCCESS=0
 EXIT_INVALID_MODE=1
-EXIT_SESSION_EXISTS=2
+EXIT_INVALID_SUBMODE=2
-EXIT_SESSION_NOT_EXIST=3
+EXIT_SESSION_EXISTS=3
-EXIT_ALREADY_IN_SESSION=4
+EXIT_SESSION_NOT_EXIST=4
-EXIT_INVALID_CONFIG=5
+EXIT_ALREADY_IN_SESSION=5
-EXIT_CONFIG_EXISTS=6
+EXIT_CONFIG_NOT_GENERATED=6
 EXIT_INVALID_CHOICE=7
 
 ## Functions
@@ -51,7 +53,7 @@ print_help() {
   echo >&2 "  help      |      | h      display this help message"
   echo >&2 ""
   echo >&2 "$(basename $0) attach [name]"
-  echo >&2 "  Attach to specified session. If no session name is provided, an interactive"
+  echo >&2 "  Attach to specified session. If no session name is provided, an interactive "
   echo >&2 "  selection menu is provided. Use <Ctrl-\\> to detach."
   echo >&2 ""
   echo >&2 "$(basename $0) new [name]"
@@ -78,6 +80,9 @@ print_help() {
   echo >&2 ""
   echo >&2 "$(basename $0) is configured using the file '$CONFIG_FILE', which, if"
   echo >&2 "non-existent, can be initialized with '$(basename $0) config generate'."
+  echo >&2 "All sessions are logged by default in order to provide a scrollback"
+  echo >&2 "buffer at attaching. The logs are located in '${config[socket_dir]}'"
+  echo >&2 "and logs of terminated sessions may be cleared using '$(basename $0) log clear'."
 }
 
 get_available_sessions() {
@@ -91,10 +96,25 @@ get_available_sessions() {
   echo ${socket_names[@]}
 }
 
+get_available_logs() {
+  local log_paths=(${SOCKET_PREFIX}*${LOG_SUFFIX})
+  local socket_names=()
+  for spath in ${log_paths[@]}; do
+    sname=${spath##${SOCKET_PREFIX}}
+    sname=${sname%%${LOG_SUFFIX}}
+    socket_names+=("${sname}")
+  done
+  echo ${socket_names[@]}
+}
+
 get_session_path() {
   echo "${SOCKET_PREFIX}${1}${SOCKET_SUFFIX}"
 }
 
+get_log_path() {
+  echo "${SOCKET_PREFIX}${1}${LOG_SUFFIX}"
+}
+
 is_existing_session_path() {  
   if [ -S $1 ]; then
     true
@@ -123,8 +143,8 @@ exit_if_in_session() {
 }
 
 exit_if_existing_session() {
-  if ! is_existing_session_name $session_name; then
+  if is_existing_session_name $session_name; then
-    echo >&2 "Session '$session_name' does not exist."
+    echo >&2 "Session '$session_name' already exists."
     exit $EXIT_SESSION_NOT_EXIST
   fi
 }
@@ -143,6 +163,13 @@ print_session_info() {
   printf "%-24s %-20s %s\n" "$session_name" "$session_time" "$session_path"
 }
 
+print_scrollback() {
+  local session_name=$1
+  local log_path=$(get_log_path $session_name)
+  printf '%*s\n' "${COLUMNS:-$(tput cols)}" '' | tr ' ' -
+  tail -n ${config[scrollback]} $log_path
+}
+
 ## Parse first argument (= mode argument)
 if [[ "$#" -lt 1 ]]; then
   print_help
@@ -175,8 +202,12 @@ case $mode in
       exit_if_nonexisting_session $session_name
     fi
     session_path=$(get_session_path $session_name)
-    CMD="dtach -a $session_path -r ${config[redraw]}"
+    CMD="dtach -a $session_path -e ${config[detach_char]} -r winch "
-    exec $CMD
+    #echo $CMD
+    echo "[attached to $session_name]"
+    [[ "${config[log_session]}" == "yes" ]] && print_scrollback $session_name 
+    eval $CMD
+    exit $EXITSUCCESS
     ;;
   "new"|"n")
     exit_if_in_session
@@ -191,9 +222,18 @@ case $mode in
     fi
     session_path=$(get_session_path $session_name)
     CMD="env DTACH_SOCKET_PATH=$session_path DTACH_SESSION_NAME=$session_name "
-    CMD+="dtach -c $session_path -r ${config[redraw]} ${config[shell]}"
+    CMD+="dtach -c $session_path -e ${config[detach_char]} -r winch "
-    echo $CMD
+    if [[ "${config[log_session]}" == "yes" ]]; then
-    exec $CMD
+      log_path=$(get_log_path $session_name)
+      touch $log_path && chmod 600 $log_path
+      CMD+="/bin/script -q -f $log_path" 
+    else
+      CMD+="/bin/bash" 
+    fi
+    #echo $CMD
+    echo "[new session $session_name]"
+    eval $CMD
+    exit $EXITSUCCESS
     ;;
   "terminate"|"term"|"t"|"kill"|"k")
     # Check if we are in terminate/kill mode
@@ -222,13 +262,15 @@ case $mode in
     fi
     for sname in ${session_name[@]}; do
       spath=$(get_session_path $sname)
+      logpath=$(get_log_path $sname)
       PID=$(fuser $spath 2> /dev/null)
-      CMD="kill $SIGNAL $PID"
+      if [ ! -z "$PID" ]; then
-      exec $CMD
+        CMD="kill $SIGNAL $PID"
-      if [[ "$CLEANUP" -eq 1 ]]; then
+        eval $CMD
-        CMD="rm $spath"
+      else # this seems to be an orphan
-        exec $CMD
+        CLEANUP=1
       fi
+      [[ "$CLEANUP" -eq 1 ]] && rm $spath
     done
     exit $EXIT_SUCCESS
     ;;
@@ -263,11 +305,11 @@ case $mode in
   "config")
     if [[ "$1" != "generate" ]]; then
       echo >&2 "Use '$(basename $0) config generate' to generate default configuration file."
-      exit $EXIT_INVALID_CONFIG 
+      exit $EXIT_INVALID_SUBMODE
     fi
     if [ -f "$CONFIG_FILE" ]; then
       echo >&2 "Configuration file '$CONFIG_FILE' already exists. Please remove it first."
-      exit $EXIT_CONFIG_EXISTS
+      exit $EXIT_CONFIG_NOT_GENERATED
     fi
     printf "" > $CONFIG_FILE
     for key in ${!config[@]}; do
@@ -275,6 +317,19 @@ case $mode in
     done
     exit $EXIT_SUCCESS
     ;;
+  "log")
+    if [[ "$1" != "clear" ]]; then
+      echo >&2 "Use '$(basename $0) log clear' to clear all unused log files."
+      exit $EXIT_INVALID_SUBMODE 
+    fi
+    logs_avail=($(get_available_logs))
+    for sname in ${logs_avail[@]}; do
+      if ! is_existing_session_name $sname; then
+        rm $(get_log_path $sname)
+      fi
+    done
+    exit $EXIT_SUCCESS
+    ;;
   *)
     echo >&2 "Invalid mode: ${mode}"
     print_help