jbn35564@uxa.cso.uiuc.edu (J.B. Nicholson) (04/10/91)
In KSH I want to make ${PS1} take on a value where it executes a function called
PS1, but not take on the output from the function itself. Here's what I mean:
function PS1 {
shrunkhome=${PWD%${HOME}/}
case ${shrunkhome} in
${HOME}) shrunkhome=\~/ ;;
esac
HOSTNAME=$(hostname)
print -n '<'${USER}'@'${HOSTNAME%%.*}':'${shrunkhome}'> ' ;;
}
...then I want to define...
export PS1=$(PS1)
but that only works the first time I use ${PS1}. I'd like to define it as:
export PS1=[just run the function called](PS1)
but I don't know how to make that definition. I've tried having an alias
for cd:
alias -x cd='_cd'
and a function (defined before that alias was set) called _cd that basically
assigns ${PS1} to the right value somewhat similar to above, except passing
arguments to the REAL cd program (to maintain compatibility) but every time
I access cd, won't this function _cd run? Also, all my error messages come
from _cd and not cd. That's rather annoying to me. Anyways, I figure keeping
this whole thing inside ${PS1} would not void any warranties, cause any
mayhem or incompatibilities or whatever. :-)
So, basically what I'm asking is: How do I do this?
Thanks in advance,
Jeff
--
+----------------------------------------------------------------------------+
| "If you hear an onion ring - answer it." J.B. Nicholson |
+----------------------------------------------------------------------------+
| jeffo@uiuc.edu (Internet) These opinions are mine, that's all.|
+----------------------------------------------------------------------------+asg@sage.cc.purdue.edu (Bruce Varney) (04/10/91)
In article <1991Apr10.035042.3008@ux1.cso.uiuc.edu> jeffo@uiuc.edu writes: }In KSH I want to make ${PS1} take on a value where it executes a function called }PS1, but not take on the output from the function itself. Here's what I mean: } }alias -x cd='_cd' } }and a function (defined before that alias was set) called _cd that basically }assigns ${PS1} to the right value somewhat similar to above, except passing }arguments to the REAL cd program (to maintain compatibility) but every time }I access cd, won't this function _cd run? Also, all my error messages come }Thanks in advance, } Jeff Here is the scoop - there are two possibilities The first and easiest (IMHO) is to switch shells to bash. bash has a variable PROMPT_COMMAND which is a command to run before the prompt is printed. Thus you could do something line PS1="\$WD ->" PROMPT_COMMAND = "WD = `working_dir`" working_dir() { whatever you use to prune the dir name } Course if you are stuck on ksh, this will also work. Note that it will not work with csh as ksh and csh handle aliases different alias -x x=cd alias -x cd='cd_help' cd_help() { whatever you use to prune the dir name x $1 } that will work just fine (or should). Hope this helps As Always The Grand Master --------- ### ## Courtesy of Bruce Varney ### # aka -> The Grand Master # asg@sage.cc.purdue.edu ### ##### # PUCC ### # ;-) # # ;'> # ##
jbn35564@uxa.cso.uiuc.edu (J.B. Nicholson) (04/11/91)
In <10009@mentor.cc.purdue.edu> asg@sage.cc.purdue.edu (Bruce Varney) writes: >Here is the scoop - there are two possibilities >The first and easiest (IMHO) is to switch shells to bash. bash has a variable >PROMPT_COMMAND which is a command to run before the prompt is printed. This sounds very nice, but BASH has no documentation (that I know of) beyond the helpscreen, which isn't like having at least a long man page at your fingertips. When more docs become available for BASH, I'll take a serious look at it, 'till then, I'll have to stick with KSH. >Course if you are stuck on ksh, this will also work. Note that it will not work >with csh as ksh and csh handle aliases different [...description deleted...] >that will work just fine (or should). > Hope this helps > As Always > The Grand Master Well, I've tried using that idea: function simpleattempt { print -n 'this is coming from simpleattempt()' } and then: PS1='simpleattempt' will make your prompt: simpleattempt so, I tried: PS1=$(simpleattempt) But that makes ${PS1}: this is coming from simpleattempt() and I need ${PS1} to retain the value of '$(simpleattempt)' or whatever the command is to make a function run. I don't want the output of simpleattempt() to be substituted into the contents of ${PS1}, I just want ${PS1} to run that function whenever ${PS1} is called. I tried a method of doing this where cd is aliased to a function that does all the calculations necessary for the prompt string and performs the regular cd command (called _cd), but I got error messages from _cd and not cd. Also, if anything was run to reference the KSH's cd command, it would go through all my prompt string stuff slowing it down a lot. Therefore, I'm trying to keep all this prompt string modification inside of ${PS1}. If I just had a way for ${PS1} to run a function without changing the value of ${PS1}, I'd be set. Jeff -- +----------------------------------------------------------------------------+ | "If you hear an onion ring - answer it." J.B. Nicholson | +----------------------------------------------------------------------------+ | jeffo@uiuc.edu (Internet) These opinions are mine, that's all.| +----------------------------------------------------------------------------+
asg@sage.cc.purdue.edu (Bruce Varney) (04/11/91)
In article <1991Apr10.190259.9524@ux1.cso.uiuc.edu> jeffo@uiuc.edu writes: }In <10009@mentor.cc.purdue.edu> asg@sage.cc.purdue.edu (Bruce Varney) writes: } }>Here is the scoop - there are two possibilities }>The first and easiest (IMHO) is to switch shells to bash. bash has a variable }>PROMPT_COMMAND which is a command to run before the prompt is printed. } }This sounds very nice, but BASH has no documentation (that I know of) beyond }the helpscreen, which isn't like having at least a long man page at your }fingertips. When more docs become available for BASH, I'll take a serious look }at it, 'till then, I'll have to stick with KSH. Wrong Wrong Wrong There is a man page for bash. Tell you what - ftp to slc2.ins.cwru.edu and get the file /pub/(This is either gnu or bash)/bash-1.07.cwru.tar.Z uncompress and untar it It will contain the source for bash 1.07 as well as the man page which is in documentation/bash.1 Just do a: cd documentation mroff -man bash.1 > bash.man more bash.man and you will get to read the bash man page. Most of bashes functionality is just like KSH. The only differences are the additions ( and the loss of select and let, but $[] replaces let). } }>Course if you are stuck on ksh, this will also work. Note that it will not work }>with csh as ksh and csh handle aliases different }[...description deleted...] }>that will work just fine (or should). }> Hope this helps }> As Always }> The Grand Master } }Well, I've tried using that idea: } }function simpleattempt { }print -n 'this is coming from simpleattempt()' }} } }and then: } }PS1='simpleattempt' } }will make your prompt: }simpleattempt } }so, I tried: } }PS1=$(simpleattempt) try PS1=\$(simpleattempt) } }But that makes ${PS1}: }this is coming from simpleattempt() } }to be substituted into the contents of ${PS1}, I just want ${PS1} to run }that function whenever ${PS1} is called. As I said, you can use the PROMPT_COMMAND variable in bash - just look it up in the man page ;-) } }I tried a method of doing this where cd is aliased to a function that does all }the calculations necessary for the prompt string and performs the regular cd }command (called _cd), but I got error messages from _cd and not cd. Also, if }anything was run to reference the KSH's cd command, it would go through all my }prompt string stuff slowing it down a lot. So try bash!!! --------- ### ## Courtesy of Bruce Varney ### # aka -> The Grand Master # asg@sage.cc.purdue.edu ### ##### # PUCC ### # ;-) # # ;'> # ##
chet@odin.INS.CWRU.Edu (Chet Ramey) (04/11/91)
In article <10052@mentor.cc.purdue.edu> asg@sage.cc.purdue.edu (Bruce Varney) writes: >Most of bashes functionality is just like KSH. The only differences are >the additions ( and the loss of select and let, but $[] replaces let). The version of bash that Bruce describes does have `let'. Chet -- Chet Ramey Internet: chet@po.CWRU.Edu Case Western Reserve University NeXT Mail: chet@macbeth.INS.CWRU.Edu ``Now, somehow we've brought our sins back physically -- and they're pissed.''
eric@ms.uky.edu (Eric H. Herrin II) (04/12/91)
jbn35564@uxa.cso.uiuc.edu (J.B. Nicholson) writes: >In KSH I want to make ${PS1} take on a value where it executes a function called >PS1, but not take on the output from the function itself. Here's what I mean: >function PS1 { >shrunkhome=${PWD%${HOME}/} >case ${shrunkhome} in > ${HOME}) shrunkhome=\~/ ;; >esac >HOSTNAME=$(hostname) >print -n '<'${USER}'@'${HOSTNAME%%.*}':'${shrunkhome}'> ' ;; >} Try this: function _cd { unalias cd cd $1 alias cd=_cd if [ "${PWD#${HOME}}" != "${PWD}" ] then PS1='"${USER}@${HOSTNAME%%.*}:~/${PWD#${HOME}}> "' else PS1='"${USER}@${HOSTNAME%%.*}:${PWD}> "' fi } and alias cd to '_cd' as you suggested in your original article. I did test this and it does work. (ksh version 11/16/88d) You might want to put some error checking in the _cd function though. -- | Eric H. Herrin II - {rutgers,uunet}!ukma!eric, eric@ms.uky.edu |
rob@mtdiablo.Concord.CA.US (Rob Bernardo) (04/12/91)
jeffo@uiuc.edu wrote: >If I just had a way for ${PS1} to run a function without changing the value of >${PS1}, I'd be set. I don't think you can. PS1 is *evaluated* before use, but not "run". -- Rob Bernardo Mt. Diablo Software Solutions email: rob@mtdiablo.Concord.CA.US phone: (415) 827-4301