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How do I print the second line in Unix?

How do I print a second line in Unix?

3 Answers. tail displays the last line of the head output and the last line of the head output is the second line of the file. PS: As to “what’s wrong with my ‘head|tail’” command – shelltel is correct. If you break up operations into separate commands, it will become obvious why it works the way it works.

How do you grep two lines in Unix?

How do I grep for multiple patterns?

  1. Use single quotes in the pattern: grep ‘pattern*’ file1 file2.
  2. Next use extended regular expressions: egrep ‘pattern1|pattern2’ *. py.
  3. Finally, try on older Unix shells/oses: grep -e pattern1 -e pattern2 *. pl.
  4. Another option to grep two strings: grep ‘word1|word2’ input.

5 дней назад

How do we display the last second line of a file?

To look at the last few lines of a file, use the tail command. tail works the same way as head: type tail and the filename to see the last 10 lines of that file, or type tail -number filename to see the last number lines of the file. Try using tail to look at the last five lines of your .

How use awk in Unix?

Related Articles

  1. AWK Operations: (a) Scans a file line by line. (b) Splits each input line into fields. (c) Compares input line/fields to pattern. (d) Performs action(s) on matched lines.
  2. Useful For: (a) Transform data files. (b) Produce formatted reports.
  3. Programming Constructs:

31 янв. 2021 г.

How do you grep 10 lines after a line?

4 Answers. You can use the -B and -A to print lines before and after the match. Will print the 10 lines before the match, including the matching line itself. And if you need to print 10 lines of leading and trailing output context.

How do you count grep lines?

Using grep -c alone will count the number of lines that contain the matching word instead of the number of total matches. The -o option is what tells grep to output each match in a unique line and then wc -l tells wc to count the number of lines. This is how the total number of matching words is deduced.

How do you grep few lines?

For BSD or GNU grep you can use -B num to set how many lines before the match and -A num for the number of lines after the match. If you want the same number of lines before and after you can use -C num . This will show 3 lines before and 3 lines after.

How do I display the first few lines of a file in Unix?

Type the following head command to display first 10 lines of a file named “bar.txt”:

  1. head -10 bar.txt.
  2. head -20 bar.txt.
  3. sed -n 1,10p /etc/group.
  4. sed -n 1,20p /etc/group.
  5. awk ‘FNR <= 10’ /etc/passwd.
  6. awk ‘FNR <= 20’ /etc/passwd.
  7. perl -ne’1..10 and print’ /etc/passwd.
  8. perl -ne’1..20 and print’ /etc/passwd.

18 дек. 2018 г.

How do I show a file line in Unix?

Related Articles

  1. awk : $>awk ‘{if(NR==LINE_NUMBER) print $0}’ file.txt.
  2. sed : $>sed -n LINE_NUMBERp file.txt.
  3. head : $>head -n LINE_NUMBER file.txt | tail -n + LINE_NUMBER Here LINE_NUMBER is, which line number you want to print. Examples: Print a line from single file.

26 сент. 2017 г.

What does the cat command do?

The ‘cat’ [short for “concatenate“] command is one of the most frequently used commands in Linux and other operating systems. The cat command allows us to create single or multiple files, view contain of file, concatenate files and redirect output in terminal or files.

What is grep and awk?

Grep is useful if you want to quickly search for lines that match in a file. … Awk is an entire programming language built around reading CSV-style files, processing the records, and optionally printing out a result data set. It can do many things but it is not the easiest tool to use for simple tasks.

What awk means?

AWK means “Awkward”. It is typically used in response to someone describing an event that placed them in an awkward situation. For example: … Peter: AWK!

The first part starts with grep , followed by the pattern that you are searching for. After the string comes the file name that the grep searches through. The command can contain many options, pattern variations, and file names. Combine as many options as necessary to get the results you need.

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