Serial Port Problems

[Ethan Rosenberg <erosenberg@hygeiabiomedical.com>]

Dear List -

I am trying to capture data from a serial port and write it to a file.

ethan@meow:/var/www$ cat /dev/ttyS0 > scale_value.html
cat: /dev/ttyS0: Device or resource busy

root@meow:/var/www#  cat /proc/tty/driver/serial
serinfo:1.0 driver revision:

0: uart:16550A port:000003F8 irq:4 tx:90 rx:270 brk:2 RTS|CTS|DTR|DSR|CD
1: uart:16550A port:00001C90 irq:17 tx:19 rx:0 CTS|DSR|CD
2: uart:unknown port:000003E8 irq:4
3: uart:unknown port:000002E8 irq:3

root@meow:/var/www# cat /proc/interrupts
           CPU0       CPU1
  0:         42          0   IO-APIC-edge      timer
  1:          3          0   IO-APIC-edge      i8042
  4:         74         89   IO-APIC-edge      serial
  6:          2          1   IO-APIC-edge      floppy
  8:          0          1   IO-APIC-edge      rtc0
  9:          1          2   IO-APIC-fasteoi   acpi
 12:          5          0   IO-APIC-edge      i8042
 16:     148679     155632   IO-APIC-fasteoi   uhci_hcd:usb1, uhci_hcd:usb4, ehci_hcd:usb7
 17:          9          8   IO-APIC-fasteoi   uhci_hcd:usb2, uhci_hcd:usb5, i801_smbus
 18:        131        143   IO-APIC-fasteoi   uhci_hcd:usb3, ehci_hcd:usb6, uhci_hcd:usb8
 40:   54993721          0  HPET_MSI-edge      hpet2
 41:          0   53507648  HPET_MSI-edge      hpet3
 42:    1041026     920449   PCI-MSI-edge      eth0
 43:     524549     476624   PCI-MSI-edge      ahci
 44:         11          9   PCI-MSI-edge      mei_me
 45:      46800      46570   PCI-MSI-edge      i915
 46:       1488       1583   PCI-MSI-edge      snd_hda_intel
NMI:      37245      37177   Non-maskable interrupts
LOC:         16         12   Local timer interrupts
SPU:          0          0   Spurious interrupts
PMI:      37245      37177   Performance monitoring interrupts
IWI:     258822     264271   IRQ work interrupts
RTR:          0          0   APIC ICR read retries
RES:    5271209    5278411   Rescheduling interrupts
CAL:        433        693   Function call interrupts
TLB:    2917013    2903216   TLB shootdowns
TRM:          0          0   Thermal event interrupts
THR:          0          0   Threshold APIC interrupts
MCE:          0          0   Machine check exceptions
MCP:       1061       1061   Machine check polls
ERR:          0
MIS:          0

/dev/ttyS1, Line 1, UART: 16550A, Port: 0x1c90, IRQ: 17
	Baud_base: 115200, close_delay: 50, divisor: 0
	closing_wait: none
	Flags: spd_normal skip_test

root@meow:/var/www#  setserial /dev/ttyS0 -a
/dev/ttyS0, Line 0, UART: 16550A, Port: 0x03f8, IRQ: 4
	Baud_base: 115200, close_delay: 50, divisor: 0
	closing_wait: 3000
	Flags: spd_normal skip_test

How do I get rid of the busy message?

TIA

Ethan