How to tell where the file read offset by a process

source: https://unix.stackexchange.com/questions/34751/how-to-find-out-the-file-offset-of-an-opened-file

1. $ cat /proc/687705/fdinfo/36

pos:    26088
flags:  0100001

in case of symbolic links:

readlink /proc/$PID/fd/$N

2.

>lsof -o file1.st1
COMMAND   PID  USER   FD   TYPE DEVICE     OFFSET    NODE   NAME
process  24017 user1 18r   REG  253,3    0x14a85000 6330199 file1.st1

Oracle Inline Function for creating NEXT ID

PS commonly increments by 1 numerically for various transaction IDs. This ex sets a 5-char ID according to the algorithm. If current VID is:

* < 99999 - increment by 1
* = 99999 - A0000
* > A0000 - increment by 1 till A9999, then B0000
::::

-------------------------------------------------------------------------------------------------------- opt #1
CREATE OR REPLACE FUNCTION nxtvid 
(curvid varchar2) RETURN varchar2 IS
vid varchar2(5);
len integer;
BEGIN
 vid:='-----';
 len:=length(curvid) ;

 if len > 5
 then
    return vid;
  end if;

select decode(trim(TRANSLATE(curvid, '0123456789',' ')), null, 
             decode(curvid,'99999','A0000', lpad(curvid+1,5,'0')),
             decode(substr(curvid,2,4), '9999', chr(ascii(substr(curvid,1,1))+1)||'0000', substr(curvid,1,1)||lpad(substr(curvid,2,4)+1,4,'0'))
) into vid from dual;

RETURN vid;

exception
         WHEN OTHERS then   ::::::
END;
/

--------------------------------------------------------------------------- Opt #2
with function ni (curvid varchar2) return varchar2 as
vid varchar2(8);
begin
select decode(trim(TRANSLATE(curvid, '0123456789',' ')), null, 
             decode(curvid,'99999','A0000', lpad(curvid+1,5,'0')),
             decode(substr(curvid,2,4), '9999', chr(upper(ascii(substr(curvid,1,1)))+1)||'0000', substr(curvid,1,1)||lpad(substr(curvid,2,4)+1,4,'0')))
       into vid from dual;
return vid;            
end;            
select ni('E9999') from dual          

--------------------------------------------------------------------------------- opt #3
UPDATE /*+ WITH_PLSQL */ PS_TABLE A
set FIELD_VID =(
with function ni (curvid varchar2) return varchar2 as
vid varchar2(8);
begin
select decode(trim(TRANSLATE(curvid, '0123456789',' ')), null, 
             decode(curvid,'99999','A0000', lpad(curvid+1,5,'0')),
             decode(substr(curvid,2,4), '9999', chr(upper(ascii(substr(curvid,1,1)))+1)||'0000', substr(curvid,1,1)||lpad(substr(curvid,2,4)+1,4,'0')))
       into vid from dual;
return vid;            
end;            
select ni('X0022') from dual
)