What exactly is the linear whitespace? (LWS/LWSP)
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I saw mention of the term, along with CRLF, CR, LF, CTL (control characters) and SP (space).
If it's not the regular inline whitespace ( ), so what character(s) is it?
character special-characters whitespace
asked Jan 12 '14 at 8:24
Reflection
8571924
add a comment |
up vote
20
down vote
favorite
I saw mention of the term, along with CRLF, CR, LF, CTL (control characters) and SP (space).
If it's not the regular inline whitespace ( ), so what character(s) is it?
character special-characters whitespace
asked Jan 12 '14 at 8:24
Reflection
8571924
add a comment |
up vote
20
down vote
favorite
up vote
20
down vote
favorite
I saw mention of the term, along with CRLF, CR, LF, CTL (control characters) and SP (space).
If it's not the regular inline whitespace ( ), so what character(s) is it?
character special-characters whitespace
asked Jan 12 '14 at 8:24
Reflection
8571924
I saw mention of the term, along with CRLF, CR, LF, CTL (control characters) and SP (space).
If it's not the regular inline whitespace ( ), so what character(s) is it?
character special-characters whitespace
character special-characters whitespace
asked Jan 12 '14 at 8:24
Reflection
8571924
asked Jan 12 '14 at 8:24
Reflection
8571924
asked Jan 12 '14 at 8:24
Reflection
8571924
asked Jan 12 '14 at 8:24
Reflection
8571924
asked Jan 12 '14 at 8:24
Reflection
8571924
8571924
add a comment |
add a comment |
1 Answer
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From STD68 Augmented BNF for Syntax Specifications: ABNF
LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule permits
; lines containing only white space*
WSP = SP / HTAB ; white space
CRLF = CR LF ; Internet standard newline
SP = %x20 ; space
HTAB = %x09 ; horizontal tab
CR = %x0D ; carriage return
LF = %x0A ; linefeed
The comment on LWSP has changed in STD68 (aka RFC5234) from RFC2234 and RFC4234 and now gives advice against using this definition in new documents.
In plain English: Linear white space is: any number of spaces or horizontal tabs, and also newline (CRLF) if it is followed by at least one space or horizontal tab.
Example of strings that are linear white space:
- [SP]
- [HTAB]
- [SP][SP]
- [HTAB][HTAB]
- [SP][HTAB][SP]
- [SP][CR][LF][SP]
- [CR][LF][SP][CR][LF][SP][CR][LF][HTAB]
- [SP][CR][LF][CR][LF][SP][CR][LF][SP][CR][LF] This is TWO linear white spaces: [SP] and [SP][CR][LF][SP]. [CR][LF] is only included if it has [SP] or [HTAB] before and after.
- [SP][VTAB][SP] Two linear white spaces: [SP] and [SP], separated by a Vertical tab.
- [SP][CR][LF][CR][LF][CR][LF] Only the first [SP] is a linear white space. CRLF followed by CRLF is not part of specification
Thanks to Jukka K. Korpela for reminding me to check for obsoleted RFCs and to unwind for clarification that CRLF must be followed by a space or htab to be part of LWSP.
answered Jan 12 '14 at 8:38
some
35k116379
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1 Answer
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oldest
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1 Answer
1
active
oldest
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active
oldest
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active
oldest
votes
up vote
31
down vote
accepted
From STD68 Augmented BNF for Syntax Specifications: ABNF
LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule permits
; lines containing only white space*
WSP = SP / HTAB ; white space
CRLF = CR LF ; Internet standard newline
SP = %x20 ; space
HTAB = %x09 ; horizontal tab
CR = %x0D ; carriage return
LF = %x0A ; linefeed
The comment on LWSP has changed in STD68 (aka RFC5234) from RFC2234 and RFC4234 and now gives advice against using this definition in new documents.
In plain English: Linear white space is: any number of spaces or horizontal tabs, and also newline (CRLF) if it is followed by at least one space or horizontal tab.
Example of strings that are linear white space:
- [SP]
- [HTAB]
- [SP][SP]
- [HTAB][HTAB]
- [SP][HTAB][SP]
- [SP][CR][LF][SP]
- [CR][LF][SP][CR][LF][SP][CR][LF][HTAB]
- [SP][CR][LF][CR][LF][SP][CR][LF][SP][CR][LF] This is TWO linear white spaces: [SP] and [SP][CR][LF][SP]. [CR][LF] is only included if it has [SP] or [HTAB] before and after.
- [SP][VTAB][SP] Two linear white spaces: [SP] and [SP], separated by a Vertical tab.
- [SP][CR][LF][CR][LF][CR][LF] Only the first [SP] is a linear white space. CRLF followed by CRLF is not part of specification
Thanks to Jukka K. Korpela for reminding me to check for obsoleted RFCs and to unwind for clarification that CRLF must be followed by a space or htab to be part of LWSP.
answered Jan 12 '14 at 8:38
some
35k116379
add a comment |
up vote
31
down vote
accepted
From STD68 Augmented BNF for Syntax Specifications: ABNF
LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule permits
; lines containing only white space*
WSP = SP / HTAB ; white space
CRLF = CR LF ; Internet standard newline
SP = %x20 ; space
HTAB = %x09 ; horizontal tab
CR = %x0D ; carriage return
LF = %x0A ; linefeed
The comment on LWSP has changed in STD68 (aka RFC5234) from RFC2234 and RFC4234 and now gives advice against using this definition in new documents.
In plain English: Linear white space is: any number of spaces or horizontal tabs, and also newline (CRLF) if it is followed by at least one space or horizontal tab.
Example of strings that are linear white space:
- [SP]
- [HTAB]
- [SP][SP]
- [HTAB][HTAB]
- [SP][HTAB][SP]
- [SP][CR][LF][SP]
- [CR][LF][SP][CR][LF][SP][CR][LF][HTAB]
- [SP][CR][LF][CR][LF][SP][CR][LF][SP][CR][LF] This is TWO linear white spaces: [SP] and [SP][CR][LF][SP]. [CR][LF] is only included if it has [SP] or [HTAB] before and after.
- [SP][VTAB][SP] Two linear white spaces: [SP] and [SP], separated by a Vertical tab.
- [SP][CR][LF][CR][LF][CR][LF] Only the first [SP] is a linear white space. CRLF followed by CRLF is not part of specification
Thanks to Jukka K. Korpela for reminding me to check for obsoleted RFCs and to unwind for clarification that CRLF must be followed by a space or htab to be part of LWSP.
answered Jan 12 '14 at 8:38
some
35k116379
add a comment |
up vote
31
down vote
accepted
up vote
31
down vote
accepted
From STD68 Augmented BNF for Syntax Specifications: ABNF
LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule permits
; lines containing only white space*
WSP = SP / HTAB ; white space
CRLF = CR LF ; Internet standard newline
SP = %x20 ; space
HTAB = %x09 ; horizontal tab
CR = %x0D ; carriage return
LF = %x0A ; linefeed
The comment on LWSP has changed in STD68 (aka RFC5234) from RFC2234 and RFC4234 and now gives advice against using this definition in new documents.
In plain English: Linear white space is: any number of spaces or horizontal tabs, and also newline (CRLF) if it is followed by at least one space or horizontal tab.
Example of strings that are linear white space:
- [SP]
- [HTAB]
- [SP][SP]
- [HTAB][HTAB]
- [SP][HTAB][SP]
- [SP][CR][LF][SP]
- [CR][LF][SP][CR][LF][SP][CR][LF][HTAB]
- [SP][CR][LF][CR][LF][SP][CR][LF][SP][CR][LF] This is TWO linear white spaces: [SP] and [SP][CR][LF][SP]. [CR][LF] is only included if it has [SP] or [HTAB] before and after.
- [SP][VTAB][SP] Two linear white spaces: [SP] and [SP], separated by a Vertical tab.
- [SP][CR][LF][CR][LF][CR][LF] Only the first [SP] is a linear white space. CRLF followed by CRLF is not part of specification
Thanks to Jukka K. Korpela for reminding me to check for obsoleted RFCs and to unwind for clarification that CRLF must be followed by a space or htab to be part of LWSP.
answered Jan 12 '14 at 8:38
some
35k116379
From STD68 Augmented BNF for Syntax Specifications: ABNF
LWSP = *(WSP / CRLF WSP) ; Use of this linear-white-space rule permits
; lines containing only white space*
WSP = SP / HTAB ; white space
CRLF = CR LF ; Internet standard newline
SP = %x20 ; space
HTAB = %x09 ; horizontal tab
CR = %x0D ; carriage return
LF = %x0A ; linefeed
The comment on LWSP has changed in STD68 (aka RFC5234) from RFC2234 and RFC4234 and now gives advice against using this definition in new documents.
In plain English: Linear white space is: any number of spaces or horizontal tabs, and also newline (CRLF) if it is followed by at least one space or horizontal tab.
Example of strings that are linear white space:
- [SP]
- [HTAB]
- [SP][SP]
- [HTAB][HTAB]
- [SP][HTAB][SP]
- [SP][CR][LF][SP]
- [CR][LF][SP][CR][LF][SP][CR][LF][HTAB]
- [SP][CR][LF][CR][LF][SP][CR][LF][SP][CR][LF] This is TWO linear white spaces: [SP] and [SP][CR][LF][SP]. [CR][LF] is only included if it has [SP] or [HTAB] before and after.
- [SP][VTAB][SP] Two linear white spaces: [SP] and [SP], separated by a Vertical tab.
- [SP][CR][LF][CR][LF][CR][LF] Only the first [SP] is a linear white space. CRLF followed by CRLF is not part of specification
Thanks to Jukka K. Korpela for reminding me to check for obsoleted RFCs and to unwind for clarification that CRLF must be followed by a space or htab to be part of LWSP.
answered Jan 12 '14 at 8:38
some
35k116379
edited Nov 11 at 23:05
answered Jan 12 '14 at 8:38
some
35k116379
answered Jan 12 '14 at 8:38
some
35k116379
answered Jan 12 '14 at 8:38
some
35k116379
35k116379
add a comment |
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