How do I remove a specific pattern from a Unix file?

How do I remove a specific pattern from a Unix file?

Unix Sed Command to Delete Lines in File – 15 Examples

1. Sed Command to Delete Lines: Sed command can be used to delete or remove specific lines which matches a given pattern or in a particular position in a file.
2. Delete first line or header line.
3. Delete last line or footer line or trailer line.
4. Delete particular line.

How do you remove a line in Unix?

Deleting a Line

1. Press the Esc key to go to normal mode.
2. Place the cursor on the line you want to delete.
3. Type dd and hit Enter to remove the line.

How do I delete a file with a pattern?

The rm command can remove multiple files at once either by passing it more than one file or by using a pattern. In the following example a pattern is used to remove all filenames ending in ‘. txt’. Be careful that no unwanted files are removed using this method.

How do you delete the first and last line in Unix?

How it works :

1. -i option edit the file itself. You could also remove that option and redirect the output to a new file or another command if you want.
2. 1d deletes the first line ( 1 to only act on the first line, d to delete it)
3. $d deletes the last line ( $ to only act on the last line, d to delete it)

How do I delete all files except?

1. To delete all files in a directory except filename, type the command below: $ rm -v !(“filename”) Delete All Files Except One File in Linux.
2. To delete all files with the exception of filename1 and filename2: $ rm -v !(“filename1″|”filename2”) Delete All Files Except Few Files in Linux.

How to delete a pattern in a Unix file?

Delete only the next line containing the pattern ‘Unix’, not the very line: Using the substitution command s, we delete from the newline character till the end, which effective deletes the next line after the line containing the pattern Unix. 23. Delete the line containing the pattern ‘Linux’, also the line before the pattern:

How to delete a line in a Unix file?

1 Delete the 1st line or the header line: $ sed ‘1d’ file Unix Linux Solaris AIX d command is to delete a line. 2 Delete a particular line, 3rd line in this case: $ sed ‘3d’ file Cygwin Unix Solaris AIX 3 Delete the last line or the trailer line of the file: $ sed ‘$d’ file Cygwin Unix Linux Solaris $ indicates the last line.

How do you delete a line in a pattern?

A little tricky ones. In order to delete the line prior to the pattern,we store every line in a buffer called as hold space. Whenever the pattern matches, we delete the content present in both, the pattern space which contains the current line, the hold space which contains the previous line.

How to delete the last line in a SED?

Delete the last line ONLY if it contains the pattern ‘AIX’: $ is for the last line. To delete a particular line only if it contains the pattern AIX, put the line number in place of the $. This is how we can implement the ‘if’ condition in sed. 19. Delete the last line ONLY if it contains either the pattern ‘AIX’ or ‘HPUX’: 20.