How do I read one line at a time in bash?

The syntax is as follows for bash, ksh, zsh, and all other shells to read a file line by line: while read -r line; do COMMAND; done < input. file.

How do you read each line in a file in Linux?

We use the read command with -r argument to read the contents without escaping the backslash character. We read the content of each line and store that in the variable line and inside the while loop we echo with a formatted -e argument to use special characters like \n and print the contents of the line variable.

Do While bash read line?

The following syntax is used for bash shell to read a file using while loop:

  1. while read -r line; do. echo “$line” ; done < input.file.
  2. while IFS= read -r line; do. echo $line; done < input.file.
  3. $ while read line; do. echo $line; done < OS.txt.
  4. #!/bin/bash. filename=’OS.txt’ n=1.
  5. #!/bin/bash. filename=$1. while read line; do.

How do I read a file in a bash script?

Reading File Content Using Script

  1. #!/bin/bash.
  2. file=’read_file.txt’
  3. i=1.
  4. while read line; do.
  5. #Reading each line.
  6. echo “Line No. $ i : $line”
  7. i=$((i+1))
  8. done < $file.

How do I go to a specific line in a file in bash?

  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.

How do I grep a specific line from a file?

The grep command searches through the file, looking for matches to the pattern specified. To use it type grep , then the pattern we’re searching for and finally the name of the file (or files) we’re searching in. The output is the three lines in the file that contain the letters ‘not’.

How do I read a file from a while loop?

Different Ways to Read File in Bash Script Using While Loop

  1. while loop should start with a while keyword followed by a condition.
  2. A condition should be enclosed within [ ] or [[ ]]. The condition should always return true for the loop to be executed.
  3. The actual block of code will be placed between do and done.

How do I split a string in bash?

In bash, a string can also be divided without using $IFS variable. The ‘readarray’ command with -d option is used to split the string data. The -d option is applied to define the separator character in the command like $IFS. Moreover, the bash loop is used to print the string in split form.