Ttyjfyk

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My body leaves; my core can stay

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Merge two greps into single one

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

3

I need to extract an ID from the output of another command. Currently my extracting command looks like:

someID=$(command | grep -oP '(?:^Successfullysbuilts)([da-z]12$)' | grep -oP '([a-zd]12)')

Example command output:

 ---> Using cache
 ---> 9b4624927fa6
Successfully built 9b4624927fa6

Expected result:

9b4624927fa6

ID extracted from line

Successfully built 9b4624927fa6

How could I merge those two grep statements into single one?

grep regular-expression

share|improve this question

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I don't really understand your question. Your command seems to do exactly what you want.
  
  – Sjoerd
  yesterday
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  
  If you are building a docker image, you can give it a name with the --tag option. That way, you can supply the name instead of having to parse it from the output. Also, --quiet supresses all output except for the image ID.
  
  – Sjoerd
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Sjoerd Yes, but they want to combine the two grep calls into a single command.
  
  – Kusalananda♦
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Sjoerd oh thanks for suggestion, will definitely try it, I need that id exactly for this reason, want to build simple automated pipeline for docker containers
  
  – stetoc
  yesterday
  

  
  
  
  

add a comment | 

3

I need to extract an ID from the output of another command. Currently my extracting command looks like:

someID=$(command | grep -oP '(?:^Successfullysbuilts)([da-z]12$)' | grep -oP '([a-zd]12)')

Example command output:

 ---> Using cache
 ---> 9b4624927fa6
Successfully built 9b4624927fa6

Expected result:

9b4624927fa6

ID extracted from line

Successfully built 9b4624927fa6

How could I merge those two grep statements into single one?

grep regular-expression

share|improve this question

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  I don't really understand your question. Your command seems to do exactly what you want.
  
  – Sjoerd
  yesterday
  

  
  
  
  


• 
  
  
  

  
  6
  

  
  
  
  
  
  

  
  
  If you are building a docker image, you can give it a name with the --tag option. That way, you can supply the name instead of having to parse it from the output. Also, --quiet supresses all output except for the image ID.
  
  – Sjoerd
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Sjoerd Yes, but they want to combine the two grep calls into a single command.
  
  – Kusalananda♦
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @Sjoerd oh thanks for suggestion, will definitely try it, I need that id exactly for this reason, want to build simple automated pipeline for docker containers
  
  – stetoc
  yesterday
  

  
  
  
  

add a comment | 

I need to extract an ID from the output of another command. Currently my extracting command looks like:

someID=$(command | grep -oP '(?:^Successfullysbuilts)([da-z]12$)' | grep -oP '([a-zd]12)')

Example command output:

 ---> Using cache
 ---> 9b4624927fa6
Successfully built 9b4624927fa6

Expected result:

9b4624927fa6

ID extracted from line

Successfully built 9b4624927fa6

How could I merge those two grep statements into single one?

grep regular-expression

share|improve this question

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

someID=$(command | grep -oP '(?:^Successfullysbuilts)([da-z]12$)' | grep -oP '([a-zd]12)')

 ---> Using cache
 ---> 9b4624927fa6
Successfully built 9b4624927fa6

9b4624927fa6

Successfully built 9b4624927fa6

share|improve this question

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

share|improve this question

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

edited 22 hours ago

John Kugelman

1,45111020

edited 22 hours ago

John Kugelman

1,45111020

asked yesterday

stetocstetoc

1184

New contributor

stetoc is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.

asked yesterday

stetocstetoc

1184

2 Answers
2

active

oldest

votes

10

A slight modification of your first grep works for me:

$ grep -oP '^SuccessfullysbuiltsK[da-z]12$' example-output
9b4624927fa6

K in PCRE resets the match start:

The escape sequence K causes any previously matched characters not to
be included in the final matched sequence.

It's similar to a zero-width positive look-behind assertion (?<=Successfully...).

share|improve this answer

edited 17 hours ago

answered yesterday

murumuru

37.6k589165

• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  K is not a look behind assertion, it just sets the start of the matched text here reported by -o. Compare echo aaaaa | grep -Po 'aK.' with echo aaaaa | grep -Po '(?<=a).' (this time using a look-behind assertion).
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas: To be fair, perlre describes it in the same list item as positive look-behind assertions, with language and typography that strongly suggests thinking of one as a variant of the other (even though that can't be the case at a technical level).
  
  – Henning Makholm
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @HenningMakholm, yes, it's unfortunate. The pcrepattern man page does not make that confusion. It's true K can often be used in place or positive look behind assertions.
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas thanks, corrected.
  
  – muru
  17 hours ago
  

  
  
  
  

add a comment | 

7

To get the hexadecimal number at the end of a line that starts with Successfully built, I would probably use sed:

sed -n -E 's/^Successfully built ([[:xdigit:]]+)$/1/p'

This replaces the matching line with the hash and prints it (and no other line).

Or awk:

awk '/^Successfully built [[:xdigit:]]+$/ print $NF '

This prints the last whitespace-delimited field of each line matching the regular expression.

In both regular expressions, the [[:xdigit:]]+ expression will match a non-empty string of hexadecimal digits.

share|improve this answer

answered yesterday

Kusalananda♦Kusalananda

141k17263439

add a comment | 

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10

A slight modification of your first grep works for me:

$ grep -oP '^SuccessfullysbuiltsK[da-z]12$' example-output
9b4624927fa6

K in PCRE resets the match start:

The escape sequence K causes any previously matched characters not to
be included in the final matched sequence.

It's similar to a zero-width positive look-behind assertion (?<=Successfully...).

share|improve this answer

edited 17 hours ago

answered yesterday

murumuru

37.6k589165

• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  K is not a look behind assertion, it just sets the start of the matched text here reported by -o. Compare echo aaaaa | grep -Po 'aK.' with echo aaaaa | grep -Po '(?<=a).' (this time using a look-behind assertion).
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas: To be fair, perlre describes it in the same list item as positive look-behind assertions, with language and typography that strongly suggests thinking of one as a variant of the other (even though that can't be the case at a technical level).
  
  – Henning Makholm
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @HenningMakholm, yes, it's unfortunate. The pcrepattern man page does not make that confusion. It's true K can often be used in place or positive look behind assertions.
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas thanks, corrected.
  
  – muru
  17 hours ago
  

  
  
  
  

add a comment | 

10

A slight modification of your first grep works for me:

$ grep -oP '^SuccessfullysbuiltsK[da-z]12$' example-output
9b4624927fa6

K in PCRE resets the match start:

The escape sequence K causes any previously matched characters not to
be included in the final matched sequence.

It's similar to a zero-width positive look-behind assertion (?<=Successfully...).

share|improve this answer

edited 17 hours ago

answered yesterday

murumuru

37.6k589165

• 
  
  
  

  
  4
  

  
  
  
  
  
  

  
  
  K is not a look behind assertion, it just sets the start of the matched text here reported by -o. Compare echo aaaaa | grep -Po 'aK.' with echo aaaaa | grep -Po '(?<=a).' (this time using a look-behind assertion).
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas: To be fair, perlre describes it in the same list item as positive look-behind assertions, with language and typography that strongly suggests thinking of one as a variant of the other (even though that can't be the case at a technical level).
  
  – Henning Makholm
  yesterday
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  @HenningMakholm, yes, it's unfortunate. The pcrepattern man page does not make that confusion. It's true K can often be used in place or positive look behind assertions.
  
  – Stéphane Chazelas
  yesterday
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StéphaneChazelas thanks, corrected.
  
  – muru
  17 hours ago
  

  
  
  
  

add a comment | 

A slight modification of your first grep works for me:

$ grep -oP '^SuccessfullysbuiltsK[da-z]12$' example-output
9b4624927fa6

K in PCRE resets the match start:

The escape sequence K causes any previously matched characters not to
be included in the final matched sequence.

It's similar to a zero-width positive look-behind assertion (?<=Successfully...).

share|improve this answer

edited 17 hours ago

answered yesterday

murumuru

37.6k589165

$ grep -oP '^SuccessfullysbuiltsK[da-z]12$' example-output
9b4624927fa6

share|improve this answer

edited 17 hours ago

answered yesterday

murumuru

37.6k589165

answered yesterday

murumuru

37.6k589165

answered yesterday

murumuru

37.6k589165

7

To get the hexadecimal number at the end of a line that starts with Successfully built, I would probably use sed:

sed -n -E 's/^Successfully built ([[:xdigit:]]+)$/1/p'

This replaces the matching line with the hash and prints it (and no other line).

Or awk:

awk '/^Successfully built [[:xdigit:]]+$/ print $NF '

This prints the last whitespace-delimited field of each line matching the regular expression.

In both regular expressions, the [[:xdigit:]]+ expression will match a non-empty string of hexadecimal digits.

share|improve this answer

answered yesterday

Kusalananda♦Kusalananda

141k17263439

add a comment | 

7

To get the hexadecimal number at the end of a line that starts with Successfully built, I would probably use sed:

sed -n -E 's/^Successfully built ([[:xdigit:]]+)$/1/p'

This replaces the matching line with the hash and prints it (and no other line).

Or awk:

awk '/^Successfully built [[:xdigit:]]+$/ print $NF '

This prints the last whitespace-delimited field of each line matching the regular expression.

In both regular expressions, the [[:xdigit:]]+ expression will match a non-empty string of hexadecimal digits.

share|improve this answer

answered yesterday

Kusalananda♦Kusalananda

141k17263439

add a comment | 

To get the hexadecimal number at the end of a line that starts with Successfully built, I would probably use sed:

sed -n -E 's/^Successfully built ([[:xdigit:]]+)$/1/p'

This replaces the matching line with the hash and prints it (and no other line).

Or awk:

awk '/^Successfully built [[:xdigit:]]+$/ print $NF '

This prints the last whitespace-delimited field of each line matching the regular expression.

In both regular expressions, the [[:xdigit:]]+ expression will match a non-empty string of hexadecimal digits.

share|improve this answer

answered yesterday

Kusalananda♦Kusalananda

141k17263439

sed -n -E 's/^Successfully built ([[:xdigit:]]+)$/1/p'

awk '/^Successfully built [[:xdigit:]]+$/ print $NF '

share|improve this answer

answered yesterday

Kusalananda♦Kusalananda

141k17263439

answered yesterday

Kusalananda♦Kusalananda

141k17263439

answered yesterday

Kusalananda♦Kusalananda

141k17263439