kcables@RELAY.NSWC.NAVY.MIL (12/12/90)
Hi everyone, I'm trying to write a shell script in which I need to find out if the 8mm tape is in the drive. Whenever I execute the mt command with the status option, the output always appears at my terminal, regardless of whether its output is redirected or piped, or even if it's in a shell script on the right side of an equal sign. Does anyone know how this output can be redirected so that I can capture the 'status' information? I tried mt -t /dev/mt/tps0d6 status > dum mt -t /dev/mt/tps0d6 status | grep Status and in a shell script: xxx=`mt -t /dev/mt/tps0d6 status` All of the above display the output at my terminal. Thanks in advance. kcables@relay.nswc.navy.mil
merritt@iris613.gsfc.nasa.gov (John H Merritt) (12/13/90)
In article <9012111454.aa09992@VGR.BRL.MIL> kcables@RELAY.NSWC.NAVY.MIL writes: >mt command with the status option, the output always appears at >my terminal, regardless of whether its output is redirected or piped, It is writing to stderr; you must also redirect stderr. > mt -t /dev/mt/tps0d6 status > dum mt -t /dev/mt/tps0d6 status >& dum > mt -t /dev/mt/tps0d6 status | grep Status mt -t /dev/mt/tps0d6 status |& grep Status > xxx=`mt -t /dev/mt/tps0d6 status` set xxx = `mt -t /dev/mt/tps0d6 status |& cat` John H. Merritt --> merritt@iris613.gsfc.nasa.gov Applied Research Corporation at NASA/GSFC "Yesterday I knew nothing, today I know that."
LEONARDZ@VM.UOGUELPH.CA (Len Zaifman) (12/13/90)
On Tue, 11 Dec 90 14:52:27 EST you said: >Hi everyone, > I'm trying to write a shell script in which I need to find >out if the 8mm tape is in the drive. Whenever I execute the >mt command with the status option, the output always appears at >my terminal, regardless of whether its output is redirected or piped, >or even if it's in a shell script on the right side of an equal sign. >Does anyone know how this output can be redirected so that I can >capture the 'status' information? I tried > > mt -t /dev/mt/tps0d6 status > dum > > mt -t /dev/mt/tps0d6 status | grep Status > > and in a shell script: > > xxx=`mt -t /dev/mt/tps0d6 status` > >All of the above display the output at my terminal. Thanks >in advance. In csh use >& to redirect the stderr output to a file : See example below : < 24 nic.uoguelph.ca /cs/leonardz> mt -t /dev/nrxb status Controller: SCSI | This Device: EXABYTE: EXB-8200 425A | appears Status: 0x200 | on Media : Not READY | terminal < 25 nic.uoguelph.ca /cs/leonardz> mt -t /dev/nrxb status >& mystat < 26 nic.uoguelph.ca /cs/leonardz> cat mystat Controller: SCSI Device: EXABYTE: EXB-8200 425A Status: 0x200 Media : Not READY < 27 nic.uoguelph.ca /cs/leonardz> > >kcables@relay.nswc.navy.mil Regards, Len Zaifman Len Zaifman Information Technology Coordinator,College of Physical and Engineering Science Department of Computing Services University of Guelph Guelph,Ontario. N1G 2W1 (519)821-4120 xt 6566 email : LeonardZ@VM.UOGUELPH.CA
kcables@RELAY.NSWC.NAVY.MIL (12/13/90)
Thanks, Len. That's what I figured out 5 minutes after I posted it. I know, read my Unix book. Kathryn