SQL> help set

 SET
 ---

 Sets a system variable to alter the SQL*Plus environment settings
 for your current session. For example, to:
     -   set the display width for data
     -   customize HTML formatting
     -   enable or disable printing of column headings
     -   set the number of lines per page
 In iSQL*Plus, you can also use the Preferences screen to set
 system variables.

 SET system_variable value

 where system_variable and value represent one of the following clauses:

   APPI[NFO]{OFF|ON|text}                   NUM[WIDTH] {10|n}
   ARRAY[SIZE] {15|n}                       PAGES[IZE] {14|n}
   AUTO[COMMIT] {OFF|ON|IMM[EDIATE]|n}      PAU[SE] {OFF|ON|text}
   AUTOP[RINT] {OFF|ON}                     RECSEP {WR[APPED]|EA[CH]|OFF}
   AUTORECOVERY {OFF|ON}                    RECSEPCHAR {_|c}
   AUTOT[RACE] {OFF|ON|TRACE[ONLY]}         SERVEROUT[PUT] {ON|OFF}
     [EXP[LAIN]] [STAT[ISTICS]]               [SIZE {n | UNLIMITED}] [FOR[MAT]
   BLO[CKTERMINATOR] {.|c|ON|OFF}             {WRA[PPED] |
   CMDS[EP] {;|c|OFF|ON}                       WOR[D_WRAPPED] |
   COLSEP {_|text}                             TRU[NCATED]}]
   CON[CAT] {.|c|ON|OFF}                   *SHIFT[INOUT] {VIS[IBLE] |
   COPYC[OMMIT] {0|n}                         INV[ISIBLE]}
   COPYTYPECHECK {ON|OFF}                  *SHOW[MODE] {OFF|ON}
   DEF[INE] {&|c|ON|OFF}                   *SQLBL[ANKLINES] {OFF|ON}
   DESCRIBE [DEPTH {1|n|ALL}]               SQLC[ASE] {MIX[ED] |
     [LINENUM {OFF|ON}] [INDENT {OFF|ON}]     LO[WER] | UP[PER]}
   ECHO {OFF|ON}                           *SQLCO[NTINUE] {> | text}
  *EDITF[ILE] file_name[.ext]              *SQLN[UMBER] {ON|OFF}
   EMB[EDDED] {OFF|ON}                      SQLPLUSCOMPAT[IBILITY] {x.y[.z]}
   ESC[APE] {\|c|OFF|ON}                   *SQLPRE[FIX] {#|c}
   FEED[BACK] {6|n|ON|OFF}                 *SQLP[ROMPT] {SQL>|text}
   FLAGGER {OFF|ENTRY|INTERMED[IATE]|FULL}  SQLT[ERMINATOR] {;|c|ON|OFF}
  *FLU[SH] {ON|OFF}                        *SUF[FIX] {SQL|text}
   HEA[DING] {ON|OFF}                      *TAB {ON|OFF}
   HEADS[EP] {||c|ON|OFF}                  *TERM[OUT] {ON|OFF}
   INSTANCE [instance_path|LOCAL]          *TI[ME] {OFF|ON}
   LIN[ESIZE] {80|n} ({150|n} iSQL*Plus)    TIMI[NG] {OFF|ON}
   LOBOF[FSET] {1|n}                       *TRIM[OUT] {ON|OFF}
   LOGSOURCE [pathname]                    *TRIMS[POOL] {OFF|ON}
   LONG {80|n}                              UND[ERLINE] {-|c|ON|OFF}
   LONGC[HUNKSIZE] {80|n}                   VER[IFY] {ON|OFF}
   MARK[UP] HTML [OFF|ON]                   WRA[P] {ON|OFF}
     [HEAD text] [BODY text] [TABLE text]   XQUERY {BASEURI text|
     [ENTMAP {ON|OFF}]                        ORDERING{UNORDERED|
     [SPOOL {OFF|ON}]                                  ORDERED|DEFAULT}|
     [PRE[FORMAT] {OFF|ON}]                   NODE{BYVALUE|BYREFERENCE|
   NEWP[AGE] {1|n|NONE}                            DEFAULT}|
   NULL text                                  CONTEXT text}
   NUMF[ORMAT] format


 An asterisk (*) indicates the SET option is not supported in iSQL*Plus.

oracle@bcm-laptop:~/sql$ cat id9.sql
sqlplus -s dbadmin/admindb
set term off echo off markup html on
spool html.lis
SELECT EXTRACT (DAY    FROM (END_DATE-BEG_DATE))*24*60*60+
       EXTRACT (HOUR   FROM (END_DATE-BEG_DATE))*60*60+
       EXTRACT (MINUTE FROM (END_DATE-BEG_DATE))*60+
       EXTRACT (SECOND FROM (END_DATE-BEG_DATE)) DELTA
from holder
/
spool off
exit
oracle@bcm-laptop:~/sql$ vi id9.sql
oracle@bcm-laptop:~/sql$ sh -x id9.sql
+ sqlplus -s dbadmin/admindb
<p>
<table border='1' width='90%' align='center' summary='Script output'>
<tr>
<th scope="col">
DELTA
</th>
</tr>
<tr>
<td align="right">
 2768398.5
</td>
</tr>
</table>
<p>