Ok, I fixed it. Apparently cat command overwrites the conf file. I copied it again and ibterm works.
miti@miti-System-Product-Name:~$ ibterm -d 18
Attempting to open /dev/gpib0
pad = 18, sad = 0, timeout = 10, send_eoi = 1, eos_mode = 0x0000
ibterm>*id
HP8594E
ibterm>ibterm>cat *
ibterm>cat*
INTERNAL: 4830 238062
C_ONLV 34
ibterm>cat on*
ON EVENTS:
ONEOS UNDEFINED
ONSWP UNDEFINED
TRMATH UNDEFINED
ONCYCLE UNDEFINED
ONDELAY UNDEFINED
ONMKR UNDEFINED
ONSRQ UNDEFINED
ONTIME UNDEFINED
ONPWRUP UNDEFINED
ibterm>cat reg*
ST/TR REG:
ST1 CF: 1.65 GHz SP: 10.00 kHz
ST2 CF: 1.65 GHz SP: 20.00 kHz
ST3 CF: 1.45 GHz SP: 2.900 GHz
ST4 CF: 1.45 GHz SP: 2.900 GHz
ST5 CF: 1.45 GHz SP: 2.900 GHz
ST6 CF: 1.45 GHz SP: 2.900 GHz
ST7 CF: 1.63 GHz SP: 10.00 kHz
ST8 CF: 1.45 GHz SP: 2.900 GHz
TR0 TL: 07:55:52 FEB 23, 1999
TR1 TL: 17:34:55 SEP 14, 2001 17:36:57 SEP 14, 2
TR2 TL: 17:34:55 SEP 14, 2001 17:36:57 SEP 14, 2
TR3 TL: 07:55:53 FEB 23, 1999
TR4 TL: 07:55:53 FEB 23, 1999
TR5 TL: 07:55:53 FEB 23, 1999
TR6 TL: 07:55:53 FEB 23, 1999
TR7 TL: 07:55:53 FEB 23, 1999
TR8 TL: 07:55:53 FEB 23, 1999
TR9 TL: 07:55:53 FEB 23, 1999
TR10 TL: 07:55:53 FEB 23, 1999
TR11 TL: 07:55:53 FEB 23, 1999
TR12 TL: 07:55:54 FEB 23, 1999
TR13 TL: 07:55:54 FEB 23, 1999
TR14 TL: 07:55:54 FEB 23, 1999
TR15 TL: 07:55:54 FEB 23, 1999
TR16 TL: 07:55:54 FEB 23, 1999
TR17 TL: 07:55:54 FEB 23, 1999
TR18 TL: 07:55:54 FEB 23, 1999
TR19 TL: 07:55:55 FEB 23, 1999
TR20 TL: 07:55:55 FEB 23, 1999
TR21 TL: 07:55:55 FEB 23, 1999
TR22 TL: 07:55:55 FEB 23, 1999
TR23 TL: 07:55:55 FEB 23, 1999
TR24 TL: 07:55:55 FEB 23, 1999
TR25 TL: 07:55:55 FEB 23, 1999
TR26 TL: 07:55:55 FEB 23, 1999
TR27 TL: 07:55:56 FEB 23, 1999
TR28 TL: 07:55:56 FEB 23, 1999
TR29 TL: 07:55:56 FEB 23, 1999
TR30 TL: 07:55:56 FEB 23, 1999
TR31 TL: 07:55:56 FEB 23, 1999
TR32 TL: 07:55:56 FEB 23, 1999
TR33 TL: 07:55:56 FEB 23, 1999
TR34 TL: 07:55:56 FEB 23, 1999
TR35 TL: 07:55:56 FEB 23, 1999
TR36 TL: 07:55:57 FEB 23, 1999
TR37 TL: 07:55:57 FEB 23, 1999
TR38 TL: 07:55:57 FEB 23, 1999
TR39 TL: 07:55:57 FEB 23, 1999
TR40 TL: 07:55:57 FEB 23, 1999
TR41 TL: 07:55:57 FEB 23, 1999
TR42 TL: 07:55:57 FEB 23, 1999
TR43 TL: 07:55:57 FEB 23, 1999
TR44 TL: 07:55:57 FEB 23, 1999
TR45 TL: 07:55:58 FEB 23, 1999
TR46 TL: 07:55:58 FEB 23, 1999
TR47 TL: 07:55:58 FEB 23, 1999
TR48 TL: 07:55:58 FEB 23, 1999
TR49 TL: 07:55:58 FEB 23, 1999
TR50 TL: 07:55:58 FEB 23, 1999
TR51 TL: 07:55:58 FEB 23, 1999
TR52 TL: 07:55:
ibterm>
ibterm: Done.
miti@miti-System-Product-Name:~$ spq "*id"
exit value cannot find gpib device "sp" at /home/miti/bin/gpib-lab-lib.pl line 405.
miti@miti-System-Product-Name:~$
Perl doesn't work though.