Grep pattern with Multiple lines with AND operation

user_4732608 0
Viewed 130

How can I determine a pattern exists over multiple lines with grep? below is a multiline pattern I need to check is present in the file

 Status:    True
 Type:   Master

I tried the below command but it checks multiple strings on a single line but fails for strings pattern match on multiple lines

  if cat file.txt  | grep -P '^(?=.*Status:.*True)(?=.*Type:.*Master)'; then echo "Present"; else echo "NOT FOUND"; fi

file.txt

Interface:                      vlan
Status:                         True
Type:                           Master
ID:                             104
grep awk multiline regex
4 Answers

Using gnu-grep you can do this:

grep -zoP '(?m)^\s*Status:\s+True\s+Type:\s+Master\s*' file

Status:                         True
Type:                           Master

Explanation:

  • P: Enabled PCRE regex mode
  • -z: Reads multiline input
  • -o: Prints only matched data
  • (?m) Enables MULTILINE mode so that we can use ^ before each line
  • ^: Start a line
user_5482250

With your shown samples, please try following awk program. Written and tested in GNU awk.

awk -v RS='(^|\n)Status:[[:space:]]+True\nType:[[:space:]]+Master' '
RT{
  sub(/^\n/,"",RT)
  print RT
}
'  Input_file

Explanation: Simple explanation would be setting RS(Record separator of awk) as regex (^|\n)Status:[[:space:]]+True\nType:[[:space:]]+Master(explained below) and in main program checking if RT is NOT NULL then remove new line(starting one) in RT with NULL and print value of RT to get expected output shown by OP.

user_58665800

I did it as follows:

grep -A 1 "^.*Status:.*True" test.txt | grep -B 1 "^Type:.*Master"

The -A x means "also show the x lines After the found one.
The -B y means "also show the y lines Before the found one.

So: show the "Status" line together with the next one (the "Type" one), and then show the "Type" line together with the previous one (the "Status" one).

user_42791550

You could also keep track of the previous line setting in every line at the end prev = $0 and use a pattern to match the previous and the current line.

awk  '
prev ~ /^[[:space:]]*Status:[[:space:]]*True$/ && $0 ~ /^[[:space:]]*Type:[[:space:]]*Master$/{
    printf "%s\n%s", prev, $0
}
{prev = $0}
' file.txt

Output

Status:                         True
Type:                           Master
user_54249880
Related