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.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ margin-bottom:0;
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262

74

There are two syntaxes for command substitution: with dollar-parentheses and with backticks.
Running top -p $(pidof init) and top -p `pidof init` gives the same output. Are these two ways of doing the same thing, or are there differences?

shell command-line command-substitution

share|improve this question

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

• 
  
  
  

  
  18
  

  
  
  
  
  
  

  
  
  See also: BashFAQ/082.
  
  – Dennis Williamson
  Jan 13 '11 at 16:38
  

  
  
  
  


• 
  
  
  

  
  40
  

  
  
  
  
  
  

  
  
  For a second there I thought this was a jQuery question.
  
  – David Murdoch
  Jan 13 '11 at 20:42
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The result might depend on the shell - some support both.
  
  – artdanil
  Feb 15 '11 at 22:33
  

  
  
  
  

add a comment | 

262

74

There are two syntaxes for command substitution: with dollar-parentheses and with backticks.
Running top -p $(pidof init) and top -p `pidof init` gives the same output. Are these two ways of doing the same thing, or are there differences?

shell command-line command-substitution

share|improve this question

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

• 
  
  
  

  
  18
  

  
  
  
  
  
  

  
  
  See also: BashFAQ/082.
  
  – Dennis Williamson
  Jan 13 '11 at 16:38
  

  
  
  
  


• 
  
  
  

  
  40
  

  
  
  
  
  
  

  
  
  For a second there I thought this was a jQuery question.
  
  – David Murdoch
  Jan 13 '11 at 20:42
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  The result might depend on the shell - some support both.
  
  – artdanil
  Feb 15 '11 at 22:33
  

  
  
  
  

add a comment | 

There are two syntaxes for command substitution: with dollar-parentheses and with backticks.
Running top -p $(pidof init) and top -p `pidof init` gives the same output. Are these two ways of doing the same thing, or are there differences?

shell command-line command-substitution

share|improve this question

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

share|improve this question

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

share|improve this question

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

edited Jan 12 '14 at 2:21

Gilles

552k13211291637

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

asked Jan 13 '11 at 11:02

TshepangTshepang

26.8k72188267

6 Answers
6

active

oldest

votes

352

+50

The old-style backquotes ` ` do treat backslashes and nesting a bit different. The new-style $() interprets everything in between ( ) as a command.

echo $(uname | $(echo cat))

Linux



echo `uname | `echo cat``

bash: command substitution: line 2: syntax error: unexpected end of file

echo cat

works if the nested backquotes are escaped:

echo `uname | `echo cat``

Linux

backslash fun:

echo $(echo '\')

\



echo `echo '\'`

The new-style $() applies to all POSIX-conformant shells.

As mouviciel pointed out, old-style ` ` might be necessary for older shells.

Apart from the technical point of view, the old-style ` ` has also a visual disadvantage:

• Hard to notice: I like $(program) better than `program`
  


• Easily confused with a single quote: '`'`''`''`'`''`'
  


• Not so easy to type (maybe not even on the standard layout of the keyboard)

_{(and SE uses ` ` for own purpose, it was a pain writing this answer :)}

share|improve this answer

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

• 
  
  
  

  
  8
  

  
  
  
  
  
  

  
  
  The only thing I would add, is that I call '(' a paren, not a bracket (which is '[').
  
  – Kendall Helmstetter Gelner
  Jan 13 '11 at 18:09
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Kendall: and here I thought '{' was the left bracket for all those years...
  
  – SamB
  Jan 13 '11 at 20:32
  

  
  
  
  


• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  @Sam: { } is usually called "curly brackets" or "braces" en.wikipedia.org/wiki/Braces_(punctuation)#Braces
  
  – Jørn Schou-Rode
  Jan 13 '11 at 21:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I also refer to '{' as curly braces. Though it seems odd you need to add the qualifier "curly" if you call the other things brackets... I guess it's just because they actually curl.
  
  – Kendall Helmstetter Gelner
  Jan 14 '11 at 4:23
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @slim I don't know on US/UK keyboards, but on spanish keyboards ` is a dead key, so I have to type either a double-backtick (something I usually forget I can even do) or backtick then space, which is a pain.
  
  – Darkhogg
  Apr 4 '14 at 16:39
  

  
  
  
  

 | 
show 6 more comments

40

Obvious difference I observe is that you cannot nest backticks while you can nest $(). Maybe both exist for legacy reasons. Similarly, the . and source commands are synonyms.

share|improve this answer

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

• 
  
  
  

  
  9
  

  
  
  
  
  
  

  
  
  Some Bourne-derived shells don't recognize source. Dash is one example.
  
  – Dennis Williamson
  Jan 13 '11 at 16:40
  

  
  
  
  


• 
  
  
  

  
  13
  

  
  
  
  
  
  

  
  
  That's not true. You can nest backtick to any level, just more painfully. Note that both $(...) and `...` are standard (the latter being deprecated) while . is standard but not source
  
  – Stéphane Chazelas
  Oct 25 '12 at 10:17
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Correction, only in (t)csh can they not be nested. (t)csh don't support $(...) though. They do support source (and not .) though.
  
  – Stéphane Chazelas
  Aug 1 '14 at 12:28
  

  
  
  
  

add a comment | 

27

$() does not work with old Bourne shell. But it has been years since I worked with old Bourne shell.

share|improve this answer

answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

add a comment | 

6

Another note, $() will use more system resource than using backticks, but is slightly faster.

In Mastering Unix shell scripting, Randal K. Michael had done a test in a chapter named "24 Ways to Process a File Line-by-Line".

share|improve this answer

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  This claim is nonsense. There is no reason why it should be faster as it is just using a different notation for the parser.
  
  – schily
  Sep 6 '15 at 13:17
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @schily: Maybe, I only quote from the book, you can read it for more details.
  
  – cuonglm
  Sep 6 '15 at 15:19
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  I would tend to agree with @schily...why would it take more resources?
  
  – Wildcard
  Mar 7 '16 at 23:21
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  @Wildcard, I suppose it's because $() makes your script one byte bigger than if it used ` (assuming you don't nest them and don't use backslashes within). As to which would be faster to parse, that would vary between shells and would be irrelevant as negligible compared to the cost of creating a pipe and forking of process which command substitution entails.
  
  – Stéphane Chazelas
  Dec 2 '16 at 9:45
  

  
  
  
  

add a comment | 

4

To add to what others said here, you can use the backticks to simulate inline comments:

echo foo `# I'm a comment!` bar

The output is: foo bar.

See the following for more information: https://stackoverflow.com/a/12797512 (Note also the comments below that post.)

share|improve this answer

edited May 23 '17 at 12:40

Community♦

1

answered Dec 2 '16 at 9:31

phkphk

4,11952257

add a comment | 

0

The $() syntax will not work with the old bourne shell.

With newer shells ` ` and $() are equivalent but $() is much more convenient to use when you need to nest multiple commands.

For instance :

echo $(basename $(dirname $(dirname /var/adm/sw/save )))

is easier to type and debug than :

echo `basename `dirname \`dirname /var/adm/sw/save \```

share|improve this answer

edited Jan 18 '15 at 14:25

Axel Beckert

241112

answered Feb 19 '14 at 12:36

EmmanuelEmmanuel

3,12411222

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  While $() may look nice, it is a pain when implementing a related parser because it requires a dual recursive parser.
  
  – schily
  Sep 6 '15 at 13:18
  

  
  
  
  


• 
  
  
  

  
  5
  

  
  
  
  
  
  

  
  
  @schily On the other side, what would be a shell without a good parser.
  
  – Emmanuel
  Sep 8 '15 at 15:58
  
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  The problem is that you need to know where the string ends before you call the parser. This is relatively simple with the backticks, but it is hard with brackets as they are used for various purposes in the shell. So you need the parser twice and in a way that does not exist in the Bourne Shell.
  
  – schily
  Sep 8 '15 at 20:04
  

  
  
  
  

add a comment | 

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352

+50

The old-style backquotes ` ` do treat backslashes and nesting a bit different. The new-style $() interprets everything in between ( ) as a command.

echo $(uname | $(echo cat))

Linux



echo `uname | `echo cat``

bash: command substitution: line 2: syntax error: unexpected end of file

echo cat

works if the nested backquotes are escaped:

echo `uname | `echo cat``

Linux

backslash fun:

echo $(echo '\')

\



echo `echo '\'`

The new-style $() applies to all POSIX-conformant shells.

As mouviciel pointed out, old-style ` ` might be necessary for older shells.

Apart from the technical point of view, the old-style ` ` has also a visual disadvantage:

• Hard to notice: I like $(program) better than `program`
  


• Easily confused with a single quote: '`'`''`''`'`''`'
  


• Not so easy to type (maybe not even on the standard layout of the keyboard)

_{(and SE uses ` ` for own purpose, it was a pain writing this answer :)}

share|improve this answer

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

• 
  
  
  

  
  8
  

  
  
  
  
  
  

  
  
  The only thing I would add, is that I call '(' a paren, not a bracket (which is '[').
  
  – Kendall Helmstetter Gelner
  Jan 13 '11 at 18:09
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Kendall: and here I thought '{' was the left bracket for all those years...
  
  – SamB
  Jan 13 '11 at 20:32
  

  
  
  
  


• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  @Sam: { } is usually called "curly brackets" or "braces" en.wikipedia.org/wiki/Braces_(punctuation)#Braces
  
  – Jørn Schou-Rode
  Jan 13 '11 at 21:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I also refer to '{' as curly braces. Though it seems odd you need to add the qualifier "curly" if you call the other things brackets... I guess it's just because they actually curl.
  
  – Kendall Helmstetter Gelner
  Jan 14 '11 at 4:23
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @slim I don't know on US/UK keyboards, but on spanish keyboards ` is a dead key, so I have to type either a double-backtick (something I usually forget I can even do) or backtick then space, which is a pain.
  
  – Darkhogg
  Apr 4 '14 at 16:39
  

  
  
  
  

 | 
show 6 more comments

352

+50

The old-style backquotes ` ` do treat backslashes and nesting a bit different. The new-style $() interprets everything in between ( ) as a command.

echo $(uname | $(echo cat))

Linux



echo `uname | `echo cat``

bash: command substitution: line 2: syntax error: unexpected end of file

echo cat

works if the nested backquotes are escaped:

echo `uname | `echo cat``

Linux

backslash fun:

echo $(echo '\')

\



echo `echo '\'`

The new-style $() applies to all POSIX-conformant shells.

As mouviciel pointed out, old-style ` ` might be necessary for older shells.

Apart from the technical point of view, the old-style ` ` has also a visual disadvantage:

• Hard to notice: I like $(program) better than `program`
  


• Easily confused with a single quote: '`'`''`''`'`''`'
  


• Not so easy to type (maybe not even on the standard layout of the keyboard)

_{(and SE uses ` ` for own purpose, it was a pain writing this answer :)}

share|improve this answer

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

• 
  
  
  

  
  8
  

  
  
  
  
  
  

  
  
  The only thing I would add, is that I call '(' a paren, not a bracket (which is '[').
  
  – Kendall Helmstetter Gelner
  Jan 13 '11 at 18:09
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Kendall: and here I thought '{' was the left bracket for all those years...
  
  – SamB
  Jan 13 '11 at 20:32
  

  
  
  
  


• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  @Sam: { } is usually called "curly brackets" or "braces" en.wikipedia.org/wiki/Braces_(punctuation)#Braces
  
  – Jørn Schou-Rode
  Jan 13 '11 at 21:35
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I also refer to '{' as curly braces. Though it seems odd you need to add the qualifier "curly" if you call the other things brackets... I guess it's just because they actually curl.
  
  – Kendall Helmstetter Gelner
  Jan 14 '11 at 4:23
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @slim I don't know on US/UK keyboards, but on spanish keyboards ` is a dead key, so I have to type either a double-backtick (something I usually forget I can even do) or backtick then space, which is a pain.
  
  – Darkhogg
  Apr 4 '14 at 16:39
  

  
  
  
  

 | 
show 6 more comments

The old-style backquotes ` ` do treat backslashes and nesting a bit different. The new-style $() interprets everything in between ( ) as a command.

echo $(uname | $(echo cat))

Linux



echo `uname | `echo cat``

bash: command substitution: line 2: syntax error: unexpected end of file

echo cat

works if the nested backquotes are escaped:

echo `uname | `echo cat``

Linux

backslash fun:

echo $(echo '\')

\



echo `echo '\'`

The new-style $() applies to all POSIX-conformant shells.

As mouviciel pointed out, old-style ` ` might be necessary for older shells.

Apart from the technical point of view, the old-style ` ` has also a visual disadvantage:

• Hard to notice: I like $(program) better than `program`
  


• Easily confused with a single quote: '`'`''`''`'`''`'
  


• Not so easy to type (maybe not even on the standard layout of the keyboard)

_{(and SE uses ` ` for own purpose, it was a pain writing this answer :)}

share|improve this answer

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

echo $(uname | $(echo cat))

Linux



echo `uname | `echo cat``

bash: command substitution: line 2: syntax error: unexpected end of file

echo cat

echo `uname | `echo cat``

Linux

echo $(echo '\')

\



echo `echo '\'`

share|improve this answer

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

edited Apr 13 '17 at 12:36

Community♦

1

edited Apr 13 '17 at 12:36

Community♦

1

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

answered Jan 13 '11 at 11:30

wagwag

25.9k65548

40

Obvious difference I observe is that you cannot nest backticks while you can nest $(). Maybe both exist for legacy reasons. Similarly, the . and source commands are synonyms.

share|improve this answer

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

• 
  
  
  

  
  9
  

  
  
  
  
  
  

  
  
  Some Bourne-derived shells don't recognize source. Dash is one example.
  
  – Dennis Williamson
  Jan 13 '11 at 16:40
  

  
  
  
  


• 
  
  
  

  
  13
  

  
  
  
  
  
  

  
  
  That's not true. You can nest backtick to any level, just more painfully. Note that both $(...) and `...` are standard (the latter being deprecated) while . is standard but not source
  
  – Stéphane Chazelas
  Oct 25 '12 at 10:17
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Correction, only in (t)csh can they not be nested. (t)csh don't support $(...) though. They do support source (and not .) though.
  
  – Stéphane Chazelas
  Aug 1 '14 at 12:28
  

  
  
  
  

add a comment | 

40

Obvious difference I observe is that you cannot nest backticks while you can nest $(). Maybe both exist for legacy reasons. Similarly, the . and source commands are synonyms.

share|improve this answer

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

• 
  
  
  

  
  9
  

  
  
  
  
  
  

  
  
  Some Bourne-derived shells don't recognize source. Dash is one example.
  
  – Dennis Williamson
  Jan 13 '11 at 16:40
  

  
  
  
  


• 
  
  
  

  
  13
  

  
  
  
  
  
  

  
  
  That's not true. You can nest backtick to any level, just more painfully. Note that both $(...) and `...` are standard (the latter being deprecated) while . is standard but not source
  
  – Stéphane Chazelas
  Oct 25 '12 at 10:17
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  Correction, only in (t)csh can they not be nested. (t)csh don't support $(...) though. They do support source (and not .) though.
  
  – Stéphane Chazelas
  Aug 1 '14 at 12:28
  

  
  
  
  

add a comment | 

Obvious difference I observe is that you cannot nest backticks while you can nest $(). Maybe both exist for legacy reasons. Similarly, the . and source commands are synonyms.

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edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

share|improve this answer

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

edited Nov 3 '12 at 10:28

Tshepang

26.8k72188267

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

answered Jan 13 '11 at 11:17

balkibalki

2,15842038

27

$() does not work with old Bourne shell. But it has been years since I worked with old Bourne shell.

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answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

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27

$() does not work with old Bourne shell. But it has been years since I worked with old Bourne shell.

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answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

add a comment | 

$() does not work with old Bourne shell. But it has been years since I worked with old Bourne shell.

share|improve this answer

answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

share|improve this answer

answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

answered Jan 13 '11 at 14:38

mouvicielmouviciel

1,1951012

6

Another note, $() will use more system resource than using backticks, but is slightly faster.

In Mastering Unix shell scripting, Randal K. Michael had done a test in a chapter named "24 Ways to Process a File Line-by-Line".

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edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

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  This claim is nonsense. There is no reason why it should be faster as it is just using a different notation for the parser.
  
  – schily
  Sep 6 '15 at 13:17
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @schily: Maybe, I only quote from the book, you can read it for more details.
  
  – cuonglm
  Sep 6 '15 at 15:19
  

  
  
  
  


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  I would tend to agree with @schily...why would it take more resources?
  
  – Wildcard
  Mar 7 '16 at 23:21
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  @Wildcard, I suppose it's because $() makes your script one byte bigger than if it used ` (assuming you don't nest them and don't use backslashes within). As to which would be faster to parse, that would vary between shells and would be irrelevant as negligible compared to the cost of creating a pipe and forking of process which command substitution entails.
  
  – Stéphane Chazelas
  Dec 2 '16 at 9:45
  

  
  
  
  

add a comment | 

6

Another note, $() will use more system resource than using backticks, but is slightly faster.

In Mastering Unix shell scripting, Randal K. Michael had done a test in a chapter named "24 Ways to Process a File Line-by-Line".

share|improve this answer

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  This claim is nonsense. There is no reason why it should be faster as it is just using a different notation for the parser.
  
  – schily
  Sep 6 '15 at 13:17
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @schily: Maybe, I only quote from the book, you can read it for more details.
  
  – cuonglm
  Sep 6 '15 at 15:19
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  I would tend to agree with @schily...why would it take more resources?
  
  – Wildcard
  Mar 7 '16 at 23:21
  

  
  
  
  


• 
  
  
  

  
  2
  

  
  
  
  
  
  

  
  
  @Wildcard, I suppose it's because $() makes your script one byte bigger than if it used ` (assuming you don't nest them and don't use backslashes within). As to which would be faster to parse, that would vary between shells and would be irrelevant as negligible compared to the cost of creating a pipe and forking of process which command substitution entails.
  
  – Stéphane Chazelas
  Dec 2 '16 at 9:45
  

  
  
  
  

add a comment | 

Another note, $() will use more system resource than using backticks, but is slightly faster.

In Mastering Unix shell scripting, Randal K. Michael had done a test in a chapter named "24 Ways to Process a File Line-by-Line".

share|improve this answer

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

share|improve this answer

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

edited Jun 9 '13 at 9:25

Tshepang

26.8k72188267

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314

answered Jun 7 '13 at 19:43

cuonglmcuonglm

107k25215314