skip/README.md

skip

Skip part of a file.

As head will show the top of a file up-to a number of line, so skip will do the opposite, and not show the top of the file, but will show the rest.

Additionally, it can check for whole lines matching, or for a token being present on the line.

N.B.: The skip crate used to be an implementation of Skip list, by Luo Jia / Zhouqi Jiang (source).

Usage

Skip a fixed number of lines

This example reads the file from stdin.

echo "line 1
line 2
line 3
line 4" > input.txt

skip 2 < input.txt

Will output:

line 3
line 4

Skip until a number of matching lines

The whole line must match.

This example reads the named file.

echo "alpha
beta
alpha
alpha
gamma
alpha" > input.txt

skip 2 --line alpha input.txt

Will output:

alpha
gamma
alpha

Skip lines until a number of tokens are seen

Looks for a string within a line, counting each occurance.

This example reads the file from stdin.

echo "Lorem ipsum dolor sit amet, 
consectetur adipiscing elit, 
sed do eiusmod tempor incididunt 
ut labore et dolore magna aliqua. 
Ut enim ad minim veniam, 
quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat." > input.txt

cat input.txt | skip 2 --token dolor

Will output:

Ut enim ad minim veniam, 
quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat.

It matches the first dolor on line 1, and the second on line 4 as part of the word dolore.

Skip lines until a lines with tokens are seen

Looks for a string within a line, only counting each matching line once.

This example reads the file from stdin.

echo "Lorem ipsum dolor sit amet, 
consectetur adipiscing elit, 
sed do eiusmod tempor incididunt 
ut labore et dolore magna aliqua. 
Ut enim ad minim veniam, 
quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat." > input.txt

cat input.txt | skip 4 --token m --ignore-extras

Will output:

quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat. 

Without --ignore-extras, it would have found the fourth m on line 3.

echo "Lorem ipsum dolor sit amet, 
consectetur adipiscing elit, 
sed do eiusmod tempor incididunt 
ut labore et dolore magna aliqua. 
Ut enim ad minim veniam, 
quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat." > input.txt

cat input.txt | skip 4 --token m

Outputing:

ut labore et dolore magna aliqua. 
Ut enim ad minim veniam, 
quis nostrud exercitation ullamco 
laboris nisi ut aliquip ex ea 
commodo consequat.