view a particular line of a file denoted by a number
Okay, this is probably an evident thing but it escapes me, as in it could probably be done in a much simpler way that I'm not aware of, so far.. Say there's a "file" and I want to view only what's on line number "X" of that file, what would be the solution?
here's what i can think of:
head -X < file | tail -1
sed -n Xp < file
is there anything else (or any other way) from the standard set of u开发者_Python百科nix/gnu/linux text-tools/utils?
sed -n 'Xp' theFile
, where X
is your line number and theFile
is your file.
in vi:
vi +X filename
in EMACS:
emacs +X filename
in the shell:
nl -ba -nln filename| grep '^X '
you can use context grep cgrep instead of grep
to see some lines above and below the matching line..
EXAMPLES:
print just that one line:
$ nl -ba -nln active_record.rb | grep '^111 '
111 module ConnectionAdapters
with context:
$ nl -ba -nln active_record.rb | grep -C 2 '^111 '
109 end
110
111 module ConnectionAdapters
112 extend ActiveSupport::Autoload
113
for context control in grep
check man grep
:
Context Line Control
-A NUM, --after-context=NUM
Print NUM lines of trailing context after matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given.
-B NUM, --before-context=NUM
Print NUM lines of leading context before matching lines. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given.
-C NUM, -NUM, --context=NUM
Print NUM lines of output context. Places a line containing a group separator (--) between contiguous groups of matches. With the -o or --only-matching option, this has no effect and a warning is given.
awk one-liner:
awk "NR==$X" file
bash loop:
for ((i=1; i<=X; i++)); do
read l
done < file
echo "$l"
Just use vi
vi file
When in the file type
:X
where X is the line number you want to see
However, the sed -n Xp file is a good way if you really only want to see the one line
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