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What is printf in awk?

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What is printf in awk?

So far we have used AWK’s print and printf functions to display data on standard output. But printf is much more powerful than what we have seen before. This function is borrowed from the C language and is very helpful while producing formatted output. Below is the syntax of the printf statement −

What is awk ‘{ print $3 }’?

If you notice awk ‘print $1’ prints first word of each line. If you use $3, it will print 3rd word of each line.

How do I print awk lines?

  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. To print 4th line from the file then we will run following commands.

Is printf the same as print?

The difference between printf and print is the format argument. This is an expression whose value is taken as a string; it specifies how to output each of the other arguments. It is called the format string.

How do I print columns in awk?

Printing the nth word or column in a file or line

  1. To print the fifth column, use the following command: $ awk ‘{ print $5 }’ filename.
  2. We can also print multiple columns and insert our custom string in between columns.

How do I print a Unix statement?

Specify the fileref from your FILENAME statement or FILENAME function. Issue the PRINT command from the command line of the windows whose contents you want to print. If you are sending output to a system printer or if you are using forms-based printing, then you can print the contents of more than one window.

Is awk still used?

LWN.net needs you! AWK is a text-processing language with a history spanning more than 40 years. It has a POSIX standard, several conforming implementations, and is still surprisingly relevant in 2020 — both for simple text processing tasks and for wrangling “big data”.

What is print $2?

awk ‘{ print $2; }’ prints the second field of each line. This field happens to be the process ID from the ps aux output.

How do I print multiple lines in awk?

  1. If I am reading this correctly i would want to use awk ‘NR==3 {print $1, $2}’ and just brute force the rest in a script with all the rows wanted.
  2. @Vithar91, well for the output you specified, you could use awk ‘NR==1;NR==2;NR==4’ but you might as well just use sed : sed -e 3d -e 4q filename or sed -n ‘1p;2p;4p’ .

Should I use printf or fprintf?

The difference between printf and fprintf is that printf is used to print a formatted string to a standard output which is most of the time a computer screen and fprintf is used to print a formatted string to a specific file. printf and fprintf can be used according to the task.

What is difference between printf () and fprintf ()?

The fprintf function formats and writes output to stream. It converts each entry in the argument list, if any, and writes to the stream according to the corresponding format specification in format. The printf function formats and writes output to the standard output stream, stdout .

What is NR and FNR in awk?

NR and FNR are two built-in awk variables. NR tells us the total number of records that we’ve read so far, while FNR gives us the number of records we’ve read in the current input file.