On Fri, Jan 26, 2007, James Long wrote:
>> Message: 24
>> Date: Fri, 26 Jan 2007 09:22:44 -0800
>> From: Bill Campbell <[EMAIL PROTECTED]>
>> Subject: Re: [OT] Does "~" always point to $HOME?
>> To: freebsd-questions@freebsd.org, Bill Campbell
>> Message-ID: <[EMAIL PROTECTED]>
>> Content-Type: text/plain; charset=us-ascii
>> My point isn't whether the FreeBSD /bin/sh expands it, but that not all
>> systems are FreeBSD, and that one can have problems on other *NIX systems.
>> Knowing where there may be differences, and avoiding the assumptions that a
>> program behaves the same on all systems, can help writing code that's
>> portable without surprises.
>This begs the rookie question:
>What is the portable way to determine an aribtrary user's home directory
>then, if ~username is not portable across shells?
>Does one just have to grep and awk /etc/passwd?  Is the format of
>/etc/passwd portable, such that one standard grep/awk sequence will 
>portably return the home directory for user "username"?

Probably the most portable way to do this would be to use awk.  A
simple script, homedir, might look like this:

# getting the backwhacks correct is sometimes ``interesting''
homedir=`awk -F: "/^$1:/{print \\$6}" /etc/passwd`

[ -z "$homedir" ] && {
        echo 'empty home for ' $1 2>&1
        exit 1
echo $homedir
exit 0

INTERNET:   [EMAIL PROTECTED]  Bill Campbell; Celestial Software, LLC
URL: http://www.celestial.com/  PO Box 820; 6641 E. Mercer Way
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