5.7 KiB
regular expressions
What regular expression do tools use?
| tool | regular expression type |
|---|---|
| awk | extended posix |
| csplit | basic posix |
| dbx | basic posix |
| dbxtool | basic posix |
| ed | basic posix |
| egrep | extended posix |
| emacs | emacs regular expression |
| expr | basic posix |
| grep | basic posix |
| lex | basic posix |
| more | basic posix |
| nawk | extended posix |
| nl | basic posix |
| perl | perl regular expression |
| pg | basic posix |
| rdist | basic posix |
| sed | basic posix |
| ugrep | extended posix |
| vi | basic posix |
basic posix regular expression
..
(extended) posix regular expression
+---------------+-----------+---------------+---------------------------+
| character | class | type | description |
+:==============+:==========+:==============+:==========================+
| . | all | character set | match any character |
| | | | (except newline) |
+---------------+-----------+---------------+---------------------------+
| ^ | all | anchor | start of line |
+---------------+-----------+---------------+---------------------------+
| $ | all | anchor | end of line |
+---------------+-----------+---------------+---------------------------+
| [...] | all | character set | list/range of characters |
+---------------+-----------+---------------+---------------------------+
| * | all | quantifier | zero or more occurences |
+---------------+-----------+---------------+---------------------------+
| \< | all | anchor | start of word |
+---------------+-----------+---------------+---------------------------+
| \> | all | anchor | end of word |
+---------------+-----------+---------------+---------------------------+
| \(..\) | all | backreference | remember pattern for |
| | | | referencing (positional) |
+---------------+-----------+---------------+---------------------------+
| \1..\9 | all | reference | reference to numbered |
| | | | pattern (positional) |
+---------------+-----------+---------------+---------------------------+
+---------------+-----------+---------------+---------------------------+
| + | extended | quantifier | one or more occurences |
+---------------+-----------+---------------+---------------------------+
| ? | extended | quantifier | zero or one occurence |
+---------------+-----------+---------------+---------------------------+
| \{M,N\} | extended | quantifier | M to N occurences |
+---------------+-----------+---------------+---------------------------+
| (...|...) | extended | pattern | match multiple patterns |
+---------------+-----------+---------------+---------------------------+
posix character sets
+-------------------+---------------------------------------------------+
| character set | description |
+-------------------+---------------------------------------------------+
| [:alnum:] | alphanumeric characters |
+-------------------+---------------------------------------------------+
| [:ascii:] | ascii characters |
+-------------------+---------------------------------------------------+
| [:cntrl:] | control characters (0x00..0x1F, 0x7F) |
+-------------------+---------------------------------------------------+
| [:lower:] | lower case letters |
+-------------------+---------------------------------------------------+
| [:upper:] | upper case letters |
+-------------------+---------------------------------------------------+
| [:space:] | whitespace characters including line breaks |
+-------------------+---------------------------------------------------+
| [:alpha:] | letters |
+-------------------+---------------------------------------------------+
| [:digit:] | digits |
+-------------------+---------------------------------------------------+
| [:print:] | printable characters, anything except control |
| | characters |
+-------------------+---------------------------------------------------+
| [:blank:] | space and tabulator |
+-------------------+---------------------------------------------------+
| [:graph:] | visible characters, anything except control |
| | characters and whitespace |
+-------------------+---------------------------------------------------+
| [:punct:] | punctuation characters (and symbols) |
+-------------------+---------------------------------------------------+
| [:xdigit:] | hexadecimal digits |
+-------------------+---------------------------------------------------+