Check that Oracle DB 11.2.0.2 test db is receiving connections

Logged in as oracle user this works :

Make sure ORACLE_HOME, ORACLE_SID and PATH are all set :
# echo $ORACLE_HOME
/export/home/database/11g/app/oracle/product/11.2.0/dbhome_1
# echo $ORACLE_SID
orcl
# echo $PATH
/usr/bin:/export/home/database/11g/app/oracle/product/11.2.0/dbhome_1/bin:

# $ORACLE_HOME/bin/sqlplus -s "/ as sysdba"<<! > /tmp/check_$ORACLE_SID.tom.ora
> select * from v\$database;
> exit
> !

# cat /tmp/check_$ORACLE_SID.tom.ora

     DBID NAME      CREATED   RESETLOGS_CHANGE# RESETLOGS
---------- --------- --------- ----------------- ---------
PRIOR_RESETLOGS_CHANGE# PRIOR_RES LOG_MODE     CHECKPOINT_CHANGE#
----------------------- --------- ------------ ------------------
ARCHIVE_CHANGE# CONTROL CONTROLFI CONTROLFILE_SEQUENCE# CONTROLFILE_CHANGE#
--------------- ------- --------- --------------------- -------------------
CONTROLFI OPEN_RESETL VERSION_T OPEN_MODE            PR


Command :

/bin/su - oracle -c "ORACLE_HOME=/export/home/database/11g/app/oracle/product/11.2.0/dbhome_1;export ORACLE_HOME;ORACLE_SID=orcl;export ORACLE_SID;$ORACLE_HOME/bin/sqlplus -s '/ as sysdba'<<! > /tmp/check_$ORACLE_SID.ora
select * from dual;
exit
!"