how to grep multiple lines until ; (semicolon)

Question

I'd like to grep lines starting with printf, however it could not end at that line and it can have more lines with \ (backslash). For instance,

printf("%s %s %s", \
        "one more line", \
        "second one", \
        "third one");

Yes, we can use the option -A (After) but it could include also meaningless lines as it specifies the number how many lines shall be output.

Please let me know if you have a brilliant idea to solve. Thanks.

score 2 · Answer 1 · answered Aug 28 '17 at 15:12

2

I don't know a way to do it with grep.

If you allow tools such as perl, there are more options:

perl -ne 'print if /^printf/ .. /;/' input.txt

If a line starting with printf is found, it will be printed along with all following lines until a ; is found.

Or:

perl -ne 'print if /^printf/ .. !/\\$/' input.txt

Same logic, but the stop condition is a line not ending with \.

answered Aug 28 '17 at 15:12

melpomene

81,915
7
76
137

Thanks for your answer. But I have an another, additional question. What if I want to print out its filename and linenumber in the form of quickfix(: like as grep does with the options -nH?? – windrg00 Aug 29 '17 at 14:13
@windrg00 Untested, but should be possible with `perl -ne 'print "$ARGV:$.: $_" if /^printf/ .. !/\\$/ } continue { close ARGV if eof ' ...`. – melpomene Aug 29 '17 at 18:14

score 0 · Answer 2 · answered Aug 28 '17 at 23:18

0

$ cat file
foo
printf("%s %s %s", \
        "one more line", \
        "second one", \
        "third one");
bar
$
$ awk '/printf/{f=1} f; !/\\$/{f=0}' file
printf("%s %s %s", \
        "one more line", \
        "second one", \
        "third one");
$

answered Aug 28 '17 at 23:18

Ed Morton

172,331
17
70
167

how to grep multiple lines until ; (semicolon)

2 Answers2

Linked