PARAGREP(1)PARAGREP(1)NAMEparagrep - search paragraphs in a file for patterns
SYNOPSISparagrep [ -aiotv ] [ -p eop_expression ] [ -e expression ] [ -f
exp_file ] ... [ file ] ...
or
paragrep [ -itv ] [ -p eop_expression ] expression [ file ] ...
DESCRIPTION
Paragrep is a paragraph grep utility. It searches for a series of reg‐
ular expressions in a text file (or several text files) and prints out
the paragraphs containing those expressions. Normally a paragraph is
displayed if it contains any of the expressions; this behavior can be
modified by using the -a option.
By default, a paragraph is defined as a block of text delimited by an
empty or blank line; this behavior can be altered with the -p option.
If no files are specified on the command line, paragrep searches stan‐
dard input.
OPTIONS-a The "and" option: Only display a paragraph if it con‐
tains all the regular expressions specified. The
default is to display a paragraph if it contains any of
the regular expressions specified. (See the -o option,
below.)
-e expression Adds a regular expression to the set of expressions
against which paragraphs are to be matched. More than
one -e argument may be specified. If only one expres‐
sion is specified, the -e may be omitted, as in the sec‐
ond form of the command, above.
-f expfile Specifies a file containing regular expressions, one
expression per line. Each expression in the file is
added to the set of expression against which paragraphs
are to be matched. More than one -f argument is per‐
mitted. Also, -f and -e may be specified together.
-i Considers upper- and lower-case letters to be identical
when making comparisons.
-o The "or" option: Display a paragraph if it contains any
of the regular expressions specified. Since this option
is the default, it is rarely specified on the command
line. It exists primarily to negate the effect of a
previous -a option. (e.g., If you've defined an alias
for paragrep that specifies the -a option, -o would be
necessary to force the "or" behavior.)
-p eop_expression
Specifies a regular expression to be used match para‐
graph delimiters. Any line that matches this regular
expression is assumed to delimit paragraphs without
actually being part of a paragraph (i.e., lines matching
this expression are never printed). If this option is
not specified, it defaults to `^[ \t]*$' which matches
blank or empty lines. (`\t' represents the horizontal
tab character. If you need to specify a horizontal tab,
you'll need to type the actual character; paragrep
doesn't recognize C-style metacharacters.)
-v Displays all lines that do not match specified expres‐
sions. The negation logic works on DeMorgan's Laws.
Normally, if -a is specified, paragrep uses the follow‐
ing logic to match the paragraph:
match = contains (expr1) AND contains (expr2) AND
contains (expr3) ...
Specifying -v along with -a changes this logic to:
match = lacks (expr1) OR lacks (expr2) OR lacks
(expr3) ...
Likewise, without -a or -v (i.e., using the -o option,
which is the default) the matching logic is:
match = contains (expr1) OR contains (expr1) OR
contains (expr1) ...
Negating that logic with -v causes paragrep to match
paragraphs with:
match = lacks (expr1) AND lacks (expr2) AND lacks
(expr3) ...
SEE ALSOed(1), grep(1), perl(1)BUGS
Paragrep's notion of troff directives is overly restrictive. To be
less restrictive, you must conjure up a more complicated -p value.
Paragrep reads each paragraph into a perl array before scanning it for
matches; as a result, extremely long paragraphs can suck up memory.
The logic behind how -v works can be confusing to the uninitiated.
AUTHOR
Brian M. Clapper,
http://www.clapper.org/bmc/ @@LICENSE@@
8 April 1995 PARAGREP(1)
