ac_check_user

Check if the specified UNIX user exists, if yes set your environment variable to that username else unset your environment variable

Example:

     AC_CHECK_USER(USER, [gleensalmon])
     if test x$USER = xgleensalmon; then
         bla..bla..bla..
     else
         bla..bla..bla..
     fi

Besides checking existence, this macro also set these environment variables upon completion:

     USER_HOME = home directory of user, written in /etc/passwd

AC_DEFUN([AC_CHECK_USER],[
AC_MSG_CHECKING([for user $2])
if grep ^$2: /etc/passwd > /dev/null; then
        $1=$2
        USER_HOME=`grep ^$2: /etc/passwd | sed "s/^\([[^:]]*:\)\{5\}\([[^:]]*\):[[^:]]*$/\2/"`
        AC_MSG_RESULT([yes])
else
        unset $1
        unset USER_HOME
        AC_MSG_RESULT([no])
fi;dnl
])