Re: Execute a Command in PS1 w/o Disturbing Previous Return Value?

[Philippe Troin <phil@xxxxxxxx>]

Aaron Davies <agdavi01@xxxxxxxxxxxxxx> writes:

> I'm trying to write a prompt that will do two things: include a file
> frequently re-downloaded from the web, and indicate the return status
> of the previous command. The problem is, if I cat out the file, it
> returns 0, overwriting the return status read by the %(0?%) directive,
> and guaranteeing that I will always get a prompt indicating
> success. What can I do about this?
> 
> Here's the whole line. The breakdown is: current temperature, pwd, (if
> last command successful, a green smiley, else a red frowny), prompt
> char.
> 
> export PS1='`cat /tmp/temperature`'" %m%~ %(0?."`echo
> '%{\e[1;32m%}:)%{\e[0m%}'`"."`echo \
> '%{\e[1;31m%}:(%{\e[0m%}'`") %# "
> 
> (/tmp/temperature is refreshed every five minutes by a cron job, in
> case you were wondering.)

What about:

 precmd() { 
   local r=$?
   psvar=()
   psvar=("$(< /tmp/temperature)") 
   (( $r )) && psvar=($psvar $r)
 }

 export PS1="$(print '%1v %m%~ %(2v,%{\e[1;31m%}:( [%2v]%{\e[0m%},%{\e[1;32m%}:%)%{\e[0m%}) %# ')"

I prefer "setopt printexitvalue" myself...

Phil.