Hi,

I'm using the ksh shell and I'd like to set my PS1 prompt on an AIX system to include, amongst ther things, the current time.

This was my best effort: export PS1=$(date -u +%R)'${ME}:${PWD}# '
but this only sets the time to the value when PS1 is defined and the time value doesn't actually change after that.

Any one got any ideas how to achieve this? I've tried searching the forum but can't find anything.

Thanks

Gareth

PWD, RANDOM and some other environment variables are defined by the shell to point to a function. I don't know of a function defined as a shell symbol that returns date & time.

In the korn shell try:
Then press return five or six times. There has to be code behind the call to the environment variable becuase it is dynamic.

Try quoting the whole string: export PS1='$(date -u +%R) ${ME}:${PWD}# '

Ygor's solution will work with ksh95 or pdksh. But ksh88 only expands variables...it won't do a general parse. I am not real fond of invoking the date command with each each display of the prompt.

ksh95 has a feature called discipline functions and these can be used to create dynamic variables that work like RANDOM.

Here is a solution that will work with all three versions of ksh. If we set SECONDS, it will continue to advance. So if we set it to the number of seconds since midnight it will serve as a time-of-day clock. To get from seconds-after-midnight to hours:minutes:seconds we need to do some arithmetic. If we reference a imaginary array, we can compute a subscript for it and use side effects from the subscript computation to set other variables. A single date process is used to initialize the clock, but after that the time is computed by the shell itself.

unset _h _m _s
eval $(date "+_h=%H ;_m=%M ;_s=%S")
((SECONDS = 3600*${_h#0}+60*${_m#0}+${_s#0}))
typeset -Z2 _h _m _s
_tsub="(_m=(SECONDS/60%60)) == (_h=(SECONDS/3600%24)) + (_s=(SECONDS%60))"
_timehm='${_x[_tsub]}$_h:${_m}'
_timehms='${_x[_tsub]}$_h:$_m:${_s}'

PS1="$_timehm $ "