History Variables

GNU History Library. Node: History Variables

2.4: History Variables

This section describes the externally visible variables exported by the GNU History Library.

Variable: int history_base: The logical offset of the first entry in the history list.

Variable: int history_length: The number of entries currently stored in the history list.

Variable: int max_input_history: The maximum number of history entries. This must be changed using stifle_history ().

Variable: char history_expansion_char: The character that starts a history event. The default is `!'.

Variable: char history_subst_char: The character that invokes word substitution if found at the start of a line. The default is `^'.

Variable: char history_comment_char: During tokenization, if this character is seen as the first character of a word, then it and all subsequent characters up to a newline are ignored, suppressing history expansion for the remainder of the line. This is disabled by default.

Variable: char * history_no_expand_chars: The list of characters which inhibit history expansion if found immediately following history_expansion_char. The default is whitespace and `='.

Variable: char * history_search_delimiter_chars: The list of additional characters which can delimit a history search string, in addition to whitespace, `:' and `?' in the case of a substring search. The default is empty.

Variable: int history_quotes_inhibit_expansion: If non-zero, single-quoted words are not scanned for the history expansion character. The default value is 0.

Variable: Function * history_inhibit_expansion_function: This should be set to the address of a function that takes two arguments: a char * (string) and an integer index into that string (i). It should return a non-zero value if the history expansion starting at string[i] should not be performed; zero if the expansion should be done. It is intended for use by applications like Bash that use the history expansion character for additional purposes. By default, this variable is set to NULL.