On 2006-10-12 @ 19:10:33 (week 41) José Alburquerque wrote:
> Hi all. I'm wondering if anyone knows how I might be able to execute
> the same command just before the execution of a command issued at the
> prompt of a bash shell.
>
> Currently, I have my bash prompt set up so that it displays the current
> date. If I can print the date just before each command is executed, I
> can always be able to get a sense of how long each command has taken.
>
> Anyone has any idea how I might go about printing the date just before
> the execution of each bash command? I just don't know where I would
> start. Thanks for any help.
You could use PROMPT_COMMAND for this. I do to create a sort of statusbar in my
shells (with the added help of tput).
I've copied the relevant parts of the code I wrote for that below. Just add it
to your bashrc, adjust the variables and case selectors in the "settings"
section to your own tastes and try if that's what you're looking for.
HTH
Grx HdV
#!/bin/bash
################################################################################
# Global variables
################################################################################
# Paths to external commands
TTY=/usr/bin/tty
TPUT=/usr/bin/tput
################################################################################
# Global functions
################################################################################
# Define text attributes
function define_text_attributes {
${TPUT} init
RESET="$(${TPUT} sgr0)"
BOLD="$(${TPUT} bold 1)"
DIM="$(${TPUT} dim)"
BLINK="$(${TPUT} blink 1)"
REVERSE="$(${TPUT} rev 1)"
STRIKETHROUGH="$(${TPUT} os 1)"
UNDERLINE="$(${TPUT} ul 1)"
BLACK="$(${TPUT} setaf 0)"
BLACKBG="$(${TPUT} setab 0)"
DARKGREY="$(${TPUT} bold ; ${TPUT} setaf 0)"
LIGHTGREY="$(${TPUT} setaf 7)"
LIGHTGREYBG="$(${TPUT} setab 7)"
WHITE="$(${TPUT} bold ; ${TPUT} setaf 7)"
RED="$(${TPUT} setaf 1)"
LIGHTRED="$(${TPUT} bold ; ${TPUT} setaf 1)"
REDBG="$(${TPUT} setab 1)"
GREEN="$(${TPUT} setaf 2)"
LIGHTGREEN="$(${TPUT} bold ; ${TPUT} setaf 2)"
GREENBG="$(${TPUT} setab 2)"
BROWN="$(${TPUT} setaf 3)"
BROWNBG="$(${TPUT} setab 3)"
YELLOW="$(${TPUT} bold ; ${TPUT} setaf 3)"
BLUE="$(${TPUT} setaf 4)"
LIGHTBLUE="$(${TPUT} bold ; ${TPUT} setaf 4)"
BLUEBG="$(${TPUT} setab 4)"
PURPLE="$(${TPUT} setaf 5)"
PURPLEBG="$(${TPUT} setab 5)"
PINK="$(${TPUT} bold ; ${TPUT} setaf 5)"
CYAN="$(${TPUT} setaf 6)"
LIGHTCYAN="$(${TPUT} bold ; ${TPUT} setaf 6)"
CYANBG="$(${TPUT} setab 6)"
}
# Build and print the statusbar
function print_statusbar {
TTY_LBL=""
PWD_LBL=""
PADDING=""
DT_LBL=""
case "${DELIMITER}" in
\[\] | \{\} | \<\> | \(\) ) DEL_OPEN=${DELIMITER:0:1}
DEL_CLOSE=${DELIMITER:1:1}
;;
* ) DEL_OPEN=''
DEL_CLOSE=${DELIMITER}
;;
esac
if [ "${SHOW_TTY}" = "1" ]; then
TTY_NAME=$( ${TTY} )
if [ -n "${TTY_NAME}" ]; then
TTY_LBL=${TTY_NAME#/dev/}
else
TTY_LBL="unknown"
fi
if [ -n "${DEL_OPEN}" ]; then
TTY_LBL="${DEL_OPEN}${TTY_LBL}${DEL_CLOSE}"
elif [ "${SHOW_PWD}" = "1" ]; then
TTY_LBL="${DEL_OPEN}${TTY_LBL}${DEL_CLOSE}"
fi
fi
if [ "${SHOW_PWD}" = "1" ]; then
if [ "${SHOW_DATETIME}" = "1" ]; then
PWD_LBL="${DEL_OPEN}${PWD}${DEL_CLOSE}"
elif [ -n "${DEL_OPEN}" ]; then
PWD_LBL="${DEL_OPEN}${PWD}${DEL_CLOSE}"
else
PWD_LBL=${PWD}
fi
fi
if [ "${SHOW_DATETIME}" = "1" ]; then
DT_LBL=$( date "+${DATETIME_FMT}" )
if [ -n "${DEL_OPEN}" ]; then
DT_LBL="${DEL_OPEN}${DT_LBL}${DEL_CLOSE}"
fi
fi
SPACES=$(( $( ${TPUT} cols ) - ${#TTY_LBL} - ${#PWD_LBL} - ${#DT_LBL} ))
if [ ${SPACES} -lt 0 ]; then
if [ "${CLIP_PWDTAIL}" = "1" ]; then
PWD_LBL=${PWD:0:$(( ${#PWD} + ${SPACES} - ${#CLIP_STR} ))}
PWD_LBL="${PWD_LBL}${CLIP_STR}"
else
PWD_LBL=${PWD:$(( ${#CLIP_STR} - ${SPACES} ))}
PWD_LBL="${CLIP_STR}${PWD_LBL}"
fi
if [ "${SHOW_DATETIME}" = "1" ]; then
PWD_LBL="${DEL_OPEN}${PWD_LBL}${DEL_CLOSE}"
elif [ -n "${DEL_OPEN}" ]; then
PWD_LBL="${DEL_OPEN}${PWD_LBL}${DEL_CLOSE}"
fi
else
while [ ${#PADDING} -lt ${SPACES} ]; do
PADDING="${PADDING} "
done
if [ "${SHOW_PWD}" = "1" ]; then
PWD_LBL="${PWD}${PADDING}"
if [ "${SHOW_DATETIME}" = "1" ]; then
PWD_LBL="${DEL_OPEN}${PWD_LBL}${DEL_CLOSE}"
elif [ -n "${DEL_OPEN}" ]; then
PWD_LBL="${DEL_OPEN}${PWD_LBL}${DEL_CLOSE}"
fi
else
PWD_LBL=${PADDING}
fi
fi
LABEL="${STATUSBG}${STATUSFG}${TTY_LBL}${PWD_LBL}${DT_LBL}${RESET}"
if [ "${STATUS_TOP}" = "1" ]; then
#ToDo: fix error where prompt overwrites statusbar when on first line
${TPUT} sc
${TPUT} cup 0 0
${TPUT} el
echo "${LABEL}"
${TPUT} rc
else
echo "${LABEL}"
fi
}
################################################################################
# Settings for interactive shells
################################################################################
# If running interactively, then:
if [ "$PS1" ]; then
# Variables defining properties of the statusbar
STATUS_TOP=1 # Show status on top instead of before prompt
SHOW_TTY=1 # Show name of current terminal
SHOW_PWD=1 # Show name of current working directory
SHOW_DATETIME=1 # Show current datetime
DATETIME_FMT="%a %F %T][%V/%j" # Show datetime using this format string
CLIP_PWDTAIL=0 # Clip name of PWD at head or tail
CLIP_STR="..." # String that shows PWD was clipped
DELIMITER="[]" # Delimiter to put between statusbar elements
SHOW_HISTORYNR=0 # Show history number of command in prompt
# Set prompt and statusbar attributes per user/host combination
define_text_attributes
WHO="$( whoami )@$( hostname )"
case "${WHO}" in
[EMAIL PROTECTED] ) STATUSFG=${YELLOW}
STATUSBG=${BLUEBG}
PROMPTFG=${YELLOW}
PROMPTBG=
;;
[EMAIL PROTECTED] ) STATUSFG=${YELLOW}
STATUSBG=${REDBG}
PROMPTFG=${RED}
PROMPTBG=
;;
* ) STATUSFG=${LIGHTCYAN}
STATUSBG=${BLUEBG}
PROMPTFG=${LIGHTCYAN}
PROMPTBG=
;;
esac
if [ "${SHOW_HISTORYNR}" = "1" ]; then
PS1="[EMAIL PROTECTED]: \[${RESET}\]"
else
PS1="[EMAIL PROTECTED]: \[${RESET}\]"
fi
PROMPT_COMMAND=print_statusbar
if
################################################################################
# Handy support function to find out what combinations you like best
################################################################################
# Print a list of available text attributes
function show_text_attributes {
echo ${BOLD}BOLD${RESET}
echo ${DIM}DIM${RESET}
echo ${BLINK}BLINK${RESET}
echo ${REVERSE}REVERSE${RESET}
echo ${STRIKETHROUGH}STRIKETHROUGH${RESET}
echo ${UNDERLINE}UNDERLINE${RESET}
echo ${BLACK}BLACK${RESET}
echo ${BLACKBG}BLACKBG${RESET}
echo ${DARKGREY}DARKGREY${RESET}
echo ${LIGHTGREY}LIGHTGREY${RESET}
echo ${LIGHTGREYBG}LIGHTGREYBG${RESET}
echo ${WHITE}WHITE${RESET}
echo ${RED}RED${RESET}
echo ${LIGHTRED}LIGHTRED${RESET}
echo ${REDBG}REDBG${RESET}
echo ${GREEN}GREEN${RESET}
echo ${LIGHTGREEN}LIGHTGREEN${RESET}
echo ${GREENBG}GREENBG${RESET}
echo ${BROWN}BROWN${RESET}
echo ${BROWNBG}BROWNBG${RESET}
echo ${YELLOW}YELLOW${RESET}
echo ${BLUE}BLUE${RESET}
echo ${LIGHTBLUE}LIGHTBLUE${RESET}
echo ${BLUEBG}BLUEBG${RESET}
echo ${PURPLE}PURPLE${RESET}
echo ${PURPLEBG}PURPLEBG${RESET}
echo ${PINK}PINK${RESET}
echo ${CYAN}CYAN${RESET}
echo ${LIGHTCYAN}LIGHTCYAN${RESET}
echo ${CYANBG}CYANBG${RESET}
}
