Practical UNIX

Chapter 19. Replacing or Removing Text from a File or Pipeline

Steve “Mor” Moritsugu

Extracting/removing characters by column position Replacing one string with another Special replacement capabilities in perl and awk Conditional replacement based on field values Formatting output into columns Translating characters: uppercase to lowercase Deleting punctuation or control characters Removing duplicate lines

Tip for Beginners Read about the cut command and the sed command to make simple replacements at the start of this chapter. Before you tackle regular expressions in the sed command, make sure that you are comfortable with all the regular expression rules covered in the previous chapter using the grep command.