Search for three consecutive newlines?
I know that squeezing multiple blank lines can be done using cat -s (and squeezing all blank lines can be done using tr -s 'n'), but I'm curious how to search for this condition in a stream of input.
I thought that stream-of-input | grep -qz $'nnn' would do it, but it doesn't.
Is there a way to do this search with simple tools?
In other words, read input, and exit with a zero status if three consecutive bytes are newline characters, or exit with nonzero status if EOF is reached without finding three consecutive newline characters.
grep search
asked 7 mins ago
WildcardWildcard
22.7k962164
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I know that squeezing multiple blank lines can be done using cat -s (and squeezing all blank lines can be done using tr -s 'n'), but I'm curious how to search for this condition in a stream of input.
I thought that stream-of-input | grep -qz $'nnn' would do it, but it doesn't.
Is there a way to do this search with simple tools?
In other words, read input, and exit with a zero status if three consecutive bytes are newline characters, or exit with nonzero status if EOF is reached without finding three consecutive newline characters.
grep search
asked 7 mins ago
WildcardWildcard
22.7k962164
add a comment |
I know that squeezing multiple blank lines can be done using cat -s (and squeezing all blank lines can be done using tr -s 'n'), but I'm curious how to search for this condition in a stream of input.
I thought that stream-of-input | grep -qz $'nnn' would do it, but it doesn't.
Is there a way to do this search with simple tools?
In other words, read input, and exit with a zero status if three consecutive bytes are newline characters, or exit with nonzero status if EOF is reached without finding three consecutive newline characters.
grep search
asked 7 mins ago
WildcardWildcard
22.7k962164
I know that squeezing multiple blank lines can be done using cat -s (and squeezing all blank lines can be done using tr -s 'n'), but I'm curious how to search for this condition in a stream of input.
I thought that stream-of-input | grep -qz $'nnn' would do it, but it doesn't.
Is there a way to do this search with simple tools?
In other words, read input, and exit with a zero status if three consecutive bytes are newline characters, or exit with nonzero status if EOF is reached without finding three consecutive newline characters.
grep search
grep search
asked 7 mins ago
WildcardWildcard
22.7k962164
asked 7 mins ago
WildcardWildcard
22.7k962164
asked 7 mins ago
WildcardWildcard
22.7k962164
asked 7 mins ago
WildcardWildcard
22.7k962164
asked 7 mins ago
WildcardWildcard
22.7k962164
22.7k962164
add a comment |
add a comment |
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