delete_lines

This promise assures that certain lines exactly matching regular expression patterns will not be present in a text file. If the lines are found, the default promise is to remove them (this behavior may be modified with further pattern matching in delete_select and/or changed with not_matching).

    bundle edit_line example
    {
    delete_lines:

      "olduser:.*";

    }

Note that typically, only a single line is specified in each delete_lines promise. However, you may of course have multiple promises that each delete a line.

It is also possible to specify multi-line delete_lines promises. However, these promises will only delete those lines if all the lines are present in the file in exactly the same order as specified in the promise (with no intervening lines). That is, all the lines must match as a unit for the delete_lines promise to be kept.

If the promiser contains multiple lines, then CFEngine assumes that all of the lines must exist as a contiguous block in order to be deletes. This gives preserve_block semantics to any multiline delete_lines promise.

Attributes

delete_select

Type: body delete_select

Common Body Attributes

Common body attributes are available to all body types. Full details for common body attributes can be found in the Common Body Attributes section of the Promise Types and Attributes page. The common attributes are as follows:

inherit_from

meta

delete_if_startwith_from_list

Description: Delete lines from a file if they begin with the sub-strings listed.

Note that this determination is made only on promised lines (that is, this attribute modifies the selection criteria, it does not make the initial selection).

Type: slist

Allowed input range: .*

Example:

     bundle edit_line alpha
     {
     delete_lines:
         ".*alpha.*"
        delete_select => starters;
     }

     body delete_select starters
     {
         delete_if_startwith_from_list => { "begin", "start", "init" };
     }

If the file contains the following lines, then this promise initially selects the four lines containing alpha, but is moderated by the delete_select attribute.

     start alpha igniter
     start beta igniter
     init alpha burner
     init beta burner
     stop beta igniter
     stop alpha igniter
     stop alpha burner

Thus, the promise will delete only the first and third lines of the file:

delete_if_not_startwith_from_list

Description: Delete lines from a file unless they start with the sub-strings in the list given.

Note that this determination is made only on promised lines. In other words, this attribute modifies the selection criteria, it does not make the initial selection.

Type: slist

Allowed input range: .*

Example:

     body delete_select example(s)
     {
     delete_if_not_startwith_from_list => { @(s) };
     }

delete_if_match_from_list

Description: Delete lines from a file if the lines completely match any of the anchored regular expressions listed.

Note that this attribute modifies the selection criteria, it does not make the initial selection, and the match determination is made only on promised lines.

Type: slist

Allowed input range: .*

Example:

     body delete_select example(s)
     {
     delete_if_match_from_list => { @(s) };
     }

delete_if_not_match_from_list

Description: Delete lines from a file unless the lines completely match any of the anchored regular expressions listed.

Note that this attribute modifies the selection criteria, it does not make the initial selection, and the match determination is made only on promised lines.

Type: slist

Allowed input range: .*

Example:

     body delete_select example(s)
     {
     delete_if_not_match_from_list => { @(s) };
     }

delete_if_contains_from_list

Description: Delete lines from a file if they contain the sub-strings listed.

Note that this attribute modifies the selection criteria, it does not make the initial selection, and the match determination is made only on promised lines.

Type: slist

Allowed input range: .*

Example:

     body delete_select example(s)
     {
     delete_if_contains_from_list => { @(s) };
     }

delete_if_not_contains_from_list

Description: Delete lines from the file which do not contain the sub-strings listed.

Note that this attribute modifies the selection criteria, it does not make the initial selection, and the match determination is made only on promised lines.

Type: slist

Allowed input range: .*

Example:

     body delete_select discard(s)
     {
     delete_if_not_contains_from_list => { "substring1", "substring2" };
     }

not_matching

Description: When this option is true, it negates the pattern match of the promised lines.

This makes no sense for multi-line deletions, and is therefore disallowed. Either a multi-line promiser matches and it should be removed (i.e. not_matching is false), or it does not match the whole thing and the ordered lines have no meaning anymore as an entity. In this case, the lines can be separately stated.

Note that this does not negate any condition expressed in delete_select. It only negates the match of the initially promised lines.

Type: boolean

Default value: false

Example:

    delete_lines:

      # edit /etc/passwd - account names that are not "mark" or "root"

      "(mark|root):.*" not_matching => "true";