bash shell infinite loop example

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iperf TOS option

CLIENT SPECIFIC OPTIONS

-S, --tos N               set the IP 'type of service'

The type-of-service for outgoing packets. (Many routers ignore the TOS field.)
You may specify the value in hex with a '0x' prefix, in octal with a '0' prefix, or in decimal.
For example, '0x10' hex = '020' octal = '16' decimal.
The TOS numbers specified in RFC 1349 are:

    IPTOS_LOWDELAY     minimize delay        0x10
    IPTOS_THROUGHPUT   maximize throughput   0x08
    IPTOS_RELIABILITY  maximize reliability  0x04
    IPTOS_LOWCOST      minimize cost         0x02

   0     1      2       3       4       5       6       7
+-----+-----+-----+-----+-----+-----+-----+-----+
 |   PRE               |                                   |  M   |
 |   CEDENCE    |           TOS                 |  B   |
 |                          |                                   |  Z   |
+-----+-----+-----+-----+-----+-----+-----+-----+

"PRECEDENCE" is intended to denote the importance or priority of the datagram.

The last field, labeled "MBZ" (for "must be zero") above, is currently unused.

1000   --   minimize delay ( + MBZ (0) = 1000 0 = 1 0000 = 0x10)
0100   --   maximize throughput ( + MBZ (0) = 0100 0 = 0 1000 = 0x08)
0010   --   maximize reliability ( + MBZ (0) = 0010 0 = 0 0100 = 0x04)
0001   --   minimize monetary cost ( + MBZ (0) = 0001 0 = 0 0010 = 0x02)
0000   --   normal service ( + MBZ (0) = 0000 0 = 0 0000 = 0x00)
* bit 3: minimize delay, bit 4: maximize throughput, bit 5: maximize reliability

PRECEDENCE
000 Routine
001 Priority
010 Immediate
011 Flash
100 FlashOverride
101 Critical
110 InterNetwork Control
111 Network Control


A. DOD DD173 Precedence/Priority Filed Explanations (Lowest-Highest):

Routine: (R) “…is used for all messages that justify transmission by electrical means unless the message delivery is of sufficient urgency to require higher precedence.”
Priority: (P) “…is used for all messages that require expeditious action by the addressee(s) and/or furnish essential information for the conduct of ongoing operations.”
Immediate (O) “…is reserved for messages relating to situations that gravely affect the security of National/Allied forces or populace.”
Flash (Z) “…is reserved for initial enemy contact messages or operational combat messages of extreme urgency.”
Flash Override (X) “… is reserved for messages relating to the outbreak of hostilities and/or detonation of nuclear devices.”
CRITIC/ECP “…stands for “Critical and Emergency Call Processing” and should only be used for authorized emergency communications, for example in the United States Government Emergency Telecommunications Service (GETS), the United Kingdom Government Telephone Preference Scheme (GTPS) and similar government emergency preparedness or reactionary implementations elsewhere.”
1. Network Control “…is intended to be used within a network only. The actual use and control of that designation is up to each network.”

2. Internetwork Control “…is intended for use by gateway control originators only.”

TOS (Dec)	TOS (Hex)	TOS (Bin)	TOS Precedence (Bin)	TOS Precedence (Dec)	TOS Precedence Name	TOS Delay flag	TOS Throughput flag	TOS Reliability flag	DSCP (Bin)	DSCP (Hex)	DSCP (Dec)	DSCP/PHB Class
0	0x00	00000000	000	0	Routine	0	0	0	000000	0x00	0	none
4	0x04	00000100	000	0	Routine	0	0	1	000001	0x01	1	none
8	0x08	00001000	000	0	Routine	0	1	0	000010	0x02	2	none
12	0x0C	00001100	000	0	Routine	0	1	1	000011	0x03	3	none
16	0x10	00010000	000	0	Routine	1	0	0	000100	0x04	4	none
32	0x20	00100000	001	1	Priority	0	0	0	001000	0x08	8	cs1
40	0x28	00101000	001	1	Priority	0	1	0	001010	0x0A	10	af11
48	0x30	00110000	001	1	Priority	1	0	0	001100	0x0C	12	af12
56	0x38	00111000	001	1	Priority	1	1	0	001110	0x0E	14	af13
64	0x40	01000000	010	2	Immediate	0	0	0	010000	0x10	16	cs2
72	0x48	01001000	010	2	Immediate	0	1	0	010010	0x12	18	af21
80	0x50	01010000	010	2	Immediate	1	0	0	010100	0x14	20	af22
88	0x58	01011000	010	2	Immediate	1	1	0	010110	0x16	22	af23
96	0x60	01100000	011	3	Flash	0	0	0	011000	0x18	24	cs3
104	0x68	01101000	011	3	Flash	0	1	0	011010	0x1A	26	af31
112	0x70	01110000	011	3	Flash	1	0	0	011100	0x1C	28	af32
120	0x78	01111000	011	3	Flash	1	1	0	011110	0x1E	30	af33
128	0x80	10000000	100	4	FlashOverride	0	0	0	100000	0x20	32	cs4
136	0x88	10001000	100	4	FlashOverride	0	1	0	100010	0x22	34	af41
144	0x90	10010000	100	4	FlashOverride	1	0	0	100100	0x24	36	af42
152	0x98	10011000	100	4	FlashOverride	1	1	0	100110	0x26	38	af43
160	0xA0	10100000	101	5	Critical	0	0	0	101000	0x28	40	cs5
176	0xB0	10110000	101	5	Critical	1	0	0	101100	0x2C	44	voice-admit
184	0xB8	10111000	101	5	Critical	1	1	0	101110	0x2E	46	ef
192	0xC0	11000000	110	6	InterNetwork Control	0	0	0	110000	0x30	48	cs6
224	0xE0	11100000	111	7	Network Control	0	0	0	111000	0x38	56	cs7