strings.bif.zeek¶

GLOBAL¶

Definitions of built-in functions related to string processing and manipulation.

Namespace: GLOBAL

Summary¶

Functions¶

`clean`: `function`	Replaces non-printable characters in a string with escaped sequences.
`count_substr`: `function`	Returns the number of times a substring occurs within a string
`edit`: `function`	Returns an edited version of a string that applies a special “backspace character” (usually `\x08` for backspace or `\x7f` for DEL).
`ends_with`: `function`	Returns whether a string ends with a substring.
`escape_string`: `function`	Replaces non-printable characters in a string with escaped sequences.
`find_all`: `function`	Finds all occurrences of a pattern in a string.
`find_all_ordered`: `function`	Finds all occurrences of a pattern in a string.
`find_last`: `function`	Finds the last occurrence of a pattern in a string.
`find_str`: `function`	Finds a string within another string, starting from the beginning.
`gsub`: `function`	Substitutes a given replacement string for all occurrences of a pattern in a given string.
`hexdump`: `function`	Returns a hex dump for given input data.
`is_alnum`: `function`	Returns whether a string consists entirely of alphanumeric characters.
`is_alpha`: `function`	Returns whether a string consists entirely of alphabetic characters.
`is_ascii`: `function`	Determines whether a given string contains only ASCII characters.
`is_num`: `function`	Returns whether a string consists entirely of digits.
`join_string_set`: `function`	Joins all values in the given set of strings with a separator placed between each element.
`join_string_vec`: `function`	Joins all values in the given vector of strings with a separator placed between each element.
`levenshtein_distance`: `function`	Calculates the Levenshtein distance between the two strings.
`ljust`: `function`	Returns a left-justified version of the string, padded to a specific length with a specified character.
`lstrip`: `function`	Removes all combinations of characters in the chars argument starting at the beginning of the string until first mismatch.
`remove_prefix`: `function`	Similar to lstrip(), except does the removal repeatedly if the pattern repeats at the start of the string.
`remove_suffix`: `function`	Similar to rstrip(), except does the removal repeatedly if the pattern repeats at the end of the string.
`reverse`: `function`	Returns a reversed copy of the string
`rfind_str`: `function`	The same as `find_str`, but returns the highest index matching the substring instead of the smallest.
`rjust`: `function`	Returns a right-justified version of the string, padded to a specific length with a specified character.
`rstrip`: `function`	Removes all combinations of characters in the chars argument starting at the end of the string until first mismatch.
`safe_shell_quote`: `function`	Takes a string and escapes characters that would allow execution of commands at the shell level.
`split_string`: `function`	Splits a string into an array of strings according to a pattern.
`split_string1`: `function`	Splits a string once into a two-element array of strings according to a pattern.
`split_string_all`: `function`	Splits a string into an array of strings according to a pattern.
`split_string_n`: `function`	Splits a string a given number of times into an array of strings according to a pattern.
`starts_with`: `function`	Returns whether a string starts with a substring.
`str_smith_waterman`: `function`	Uses the Smith-Waterman algorithm to find similar/overlapping substrings.
`str_split_indices`: `function`	Splits a string into substrings with the help of an index vector of cutting points.
`strcmp`: `function`	Lexicographically compares two strings.
`string_cat`: `function`	Concatenates all arguments into a single string.
`string_fill`: `function`	Generates a string of a given size and fills it with repetitions of a source string.
`string_to_ascii_hex`: `function`	Returns an ASCII hexadecimal representation of a string.
`strip`: `function`	Strips whitespace at both ends of a string.
`strstr`: `function`	Locates the first occurrence of one string in another.
`sub`: `function`	Substitutes a given replacement string for the first occurrence of a pattern in a given string.
`sub_bytes`: `function`	Get a substring from a string, given a starting position and length.
`subst_string`: `function`	Substitutes each (non-overlapping) appearance of a string in another.
`swap_case`: `function`	Swaps the case of every alphabetic character in a string.
`to_lower`: `function`	Replaces all uppercase letters in a string with their lowercase counterpart.
`to_string_literal`: `function`	Replaces non-printable characters in a string with escaped sequences.
`to_title`: `function`	Converts a string to Title Case.
`to_upper`: `function`	Replaces all lowercase letters in a string with their uppercase counterpart.
`zfill`: `function`	Returns a copy of a string filled on the left side with zeroes.

Detailed Interface¶

Functions¶

clean¶

Type: function (str: string) : string

Replaces non-printable characters in a string with escaped sequences. The mappings are:

values not in [32, 126] to \xXX

If the string does not yet have a trailing NUL, one is added internally.

In contrast to escape_string, this encoding is not fully reversible.`

Parameters: str – The string to escape.
Returns: The escaped string.

count_substr¶

Type: function (str: string, sub: string) : count

Returns the number of times a substring occurs within a string

Parameters

str – The string to search in.
substr – The string to search for.

Returns

The number of times the substring occurred.

edit¶

Type: function (arg_s: string, arg_edit_char: string) : string

Returns an edited version of a string that applies a special “backspace character” (usually \x08 for backspace or \x7f for DEL). For example, edit("hello there", "e") returns "llo t".

Parameters

arg_s – The string to edit.
arg_edit_char – A string of exactly one character that represents the “backspace character”. If it is longer than one character Zeek generates a run-time error and uses the first character in the string.

Returns

An edited version of arg_s where arg_edit_char triggers the deletion of the last character.

ends_with¶

Type: function (str: string, sub: string) : bool

Returns whether a string ends with a substring.

escape_string¶

Type: function (s: string) : string

Replaces non-printable characters in a string with escaped sequences. The mappings are:

values not in [32, 126] to \xXX

\ to \\

In contrast to clean, this encoding is fully reversible.`

Parameters: str – The string to escape.
Returns: The escaped string.