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-2

0

If run:

 true  false; echo $?

I get an exit code of 0. Does anyone know why that is?

bash shell exit-status

share|improve this question

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

add a comment | 

-2

0

If run:

 true  false; echo $?

I get an exit code of 0. Does anyone know why that is?

bash shell exit-status

share|improve this question

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

add a comment | 

If run:

 true  false; echo $?

I get an exit code of 0. Does anyone know why that is?

bash shell exit-status

share|improve this question

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

 true  false; echo $?

share|improve this question

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

share|improve this question

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

asked 1 hour ago

Alexander MillsAlexander Mills

2,42221963

2 Answers
2

active

oldest

votes

4

true  false

is equivalent to

true ' false'

It causes the shell to run true with false (including an initial space character) as its parameter. The implementation of true that you’re using ignores this parameter and exits with a zero return value.

share|improve this answer

edited 45 mins ago

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Note that the behaviour of true when given any argument is unspecified by POSIX, some implementations may very well return a syntax error and a non-zero exit status.
  
  – Stéphane Chazelas
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Backticks won't preserve the leading space. You'll have to use <code> false</code> for that.
  
  – muru
  42 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @muru <code> doesn’t either, at least not for me...
  
  – Stephen Kitt
  41 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StephenKitt hmmm, works for me: meta.stackexchange.com/a/329041/270345 Ah, well.
  
  – muru
  38 mins ago
  

  
  
  
  

 | 
show 1 more comment

3

You're just running the command true with some arguments. Since those arguments aren't options, it doesn't matter what they are.

share|improve this answer

answered 1 hour ago

murumuru

38.7k592168

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  

add a comment | 

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4

true  false

is equivalent to

true ' false'

It causes the shell to run true with false (including an initial space character) as its parameter. The implementation of true that you’re using ignores this parameter and exits with a zero return value.

share|improve this answer

edited 45 mins ago

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Note that the behaviour of true when given any argument is unspecified by POSIX, some implementations may very well return a syntax error and a non-zero exit status.
  
  – Stéphane Chazelas
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Backticks won't preserve the leading space. You'll have to use <code> false</code> for that.
  
  – muru
  42 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @muru <code> doesn’t either, at least not for me...
  
  – Stephen Kitt
  41 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StephenKitt hmmm, works for me: meta.stackexchange.com/a/329041/270345 Ah, well.
  
  – muru
  38 mins ago
  

  
  
  
  

 | 
show 1 more comment

4

true  false

is equivalent to

true ' false'

It causes the shell to run true with false (including an initial space character) as its parameter. The implementation of true that you’re using ignores this parameter and exits with a zero return value.

share|improve this answer

edited 45 mins ago

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Note that the behaviour of true when given any argument is unspecified by POSIX, some implementations may very well return a syntax error and a non-zero exit status.
  
  – Stéphane Chazelas
  46 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Backticks won't preserve the leading space. You'll have to use <code> false</code> for that.
  
  – muru
  42 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @muru <code> doesn’t either, at least not for me...
  
  – Stephen Kitt
  41 mins ago
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  @StephenKitt hmmm, works for me: meta.stackexchange.com/a/329041/270345 Ah, well.
  
  – muru
  38 mins ago
  

  
  
  
  

 | 
show 1 more comment

true  false

is equivalent to

true ' false'

It causes the shell to run true with false (including an initial space character) as its parameter. The implementation of true that you’re using ignores this parameter and exits with a zero return value.

share|improve this answer

edited 45 mins ago

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

true  false

true ' false'

share|improve this answer

edited 45 mins ago

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

answered 1 hour ago

Stephen KittStephen Kitt

189k26442520

3

You're just running the command true with some arguments. Since those arguments aren't options, it doesn't matter what they are.

share|improve this answer

answered 1 hour ago

murumuru

38.7k592168

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  

add a comment | 

3

You're just running the command true with some arguments. Since those arguments aren't options, it doesn't matter what they are.

share|improve this answer

answered 1 hour ago

murumuru

38.7k592168

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  oh duh lol thanks
  
  – Alexander Mills
  58 mins ago
  

  
  
  
  

add a comment | 

You're just running the command true with some arguments. Since those arguments aren't options, it doesn't matter what they are.

share|improve this answer

answered 1 hour ago

murumuru

38.7k592168

share|improve this answer

answered 1 hour ago

murumuru

38.7k592168

answered 1 hour ago

murumuru

38.7k592168

answered 1 hour ago

murumuru

38.7k592168