Extracting specific words using sed

Question

I have a line like this

BR_MALLOC %p File - %s, Func - %s, Line - %u\n

This is actually a line from a C program which outputs the malloced address, the file where the custom malloc BR_MALLOC was called etc etc.

Now, I am running sed on this output to get just the malloced address (%p)

I tried this regular expression

$ echo "BR_MALLOC %p File - %s, Func - %s, Line - %u\n" | sed 's/BR_MALLOC\s+\(\S+\).*/\1'

Expected Output

%p

Output I get is

BR_MALLOC %p File - %s, Func - %s, Line - %un

Where am I going wrong?

Answer 1

You might need to escape the + ( docs ):

echo "BR_MALLOC %p File - %s, Func - %s, Line - %u\n" | sed 's/BR_MALLOC\s\+\(\S\+\).*/\1/'
%p

Answer 2

不了解sed，但使用perl，你的表达式几乎可以正常工作：

perl -pe 's/BR_MALLOC\s+(\S+).*/$1/'