Diff for "BashFAQ/079"

Differences between revisions 1 and 3 (spanning 2 versions)

How can I grep for lines containing foo AND bar, foo OR bar?

The easiest way to match both foo AND bar is to use two grep commands:

grep foo | grep bar

It can also be done with one egrep, although (as you can probably guess) this doesn't really scale well to more than two patterns:

egrep 'foo.*bar|bar.*foo'

If you prefer, you can achieve this in one sed or awk statement. (The awk example is probably the most scalable.)

sed -n '/foo/{/bar/p}'
awk '/foo/ && /bar/'

To match lines containing foo OR bar, egrep is the natural choice, but it can also be done with sed, awk, etc.

egrep 'foo|bar'
# some people prefer grep -E 'foo|bar'

# This is another option, some people prefer:
grep -e 'foo' -e 'bar'

egrep is the oldest and most portable form of the grep command using Extended Regular Expressions (EREs). -E is a POSIX-required switch.

-  ⇤ ← Revision 1 as of 2007-05-03 00:16:03 → 
  Size: 478
  Editor: redondos
  Comment:
+   ← Revision 3 as of 2007-05-22 20:08:32 → ⇥
  Size: 1006
  Editor: JeremyBaron
  Comment: added grep -e 'foo' -e 'bar'
-Deletions are marked like this.
+Additions are marked like this.
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-Well, for lines containing foo AND bar, two grep statements are needed.
+The easiest way to match both foo AND bar is to use two {{{grep}}} commands:
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-grep foo| grep bar
+grep foo | grep bar
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-If you prefer, you can achieve this in one sed, or awk statement.
+It can also be done with one {{{egrep}}}, although (as you can probably guess) this doesn't really scale well to more than two patterns:

{{{
egrep 'foo.*bar|bar.*foo'
}}}

If you prefer, you can achieve this in one {{{sed}}} or {{{awk}}} statement.  (The {{{awk}}} example is probably the most scalable.)
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+Line 23:
-And for lines containing foo OR bar, grep can do it "nicely", but it can also be done with sed, awk, etc.
+To match lines containing foo OR bar, {{{egrep}}} is the natural choice, but it can also be done with {{{sed}}}, {{{awk}}}, etc.
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+Line 27:
-grep -E 'foo|bar'
+# some people prefer grep -E 'foo|bar'

# This is another option, some people prefer:
grep -e 'foo' -e 'bar'
-Line 23:
+Line 32:
+{{{egrep}}} is the oldest and most portable form of the {{{grep}}} command using Extended Regular Expressions (EREs).  {{{-E}}} is a POSIX-required switch.