Finding a part of a string in another string variable in bash

Question

I have an issue in finding a part of string variable in another string variable, I tried many methods but none worked out..

for example:

echo -e "   > Required_keyword: $required_keyword"
send_func GUI WhereAmI
echo -e "   > FUNCVALUE: $FUNCVALUE"

flag=`echo $FUNCVALUE|awk '{print match($0,"$required_keyword")}'`;

if [ $flag -gt 0 ];then

    echo "Success";
else
    echo "fail";

fi

But it always gives fail though there are certain words in variable which matches like

0_Menu/BAA_Record ($required_keyword output string)

Trying to connect to 169.254.98.226 ... OK! Executing sendFunc GUI WhereAmI Sent Function WhereAmI [OK PageName: "_0_Menu__47__BAA_Record" ($FUNCVALUE output string)

As we can see here the BAA_Record is common in both of the output still, it always give FAIL

The output echo is

   > Required_keyword: 0_Menu/BAA_Record
   > FUNCVALUE: 
Trying to connect to 169.254.98.226 ... OK!


Executing sendFunc GUI WhereAmI 
Sent Function WhereAmI [OK]
PageName: "_0_Menu__47__BAA_Record"

Shell variables do not get expanded in single quotes (like the ones you wrapped around your awk script). — Etan Reisner
– Etan Reisner, Commented Sep 18, 2014 at 13:31
Can you give the exact input string and whats your expected result? — Ram
– Ram, Commented Sep 18, 2014 at 13:31

chepner · Accepted Answer · 2014-09-18 13:36:41Z

2

Bash can do wildcard and regex matches inside double square brackets.

if [[ foobar == *oba* ]]    # wildcard

if [[ foobar =~ fo*b.r ]]   # regex

In your example:

if [[ $FUNCVALUE = *$required_keyword* ]]

if [[ $FUNCVALUE =~ .*$required_keyword.* ]]

edited Sep 18, 2014 at 13:36

chepner

538k77 gold badges594 silver badges746 bronze badges

answered Sep 18, 2014 at 13:34

John Kugelman

364k70 gold badges555 silver badges600 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

venkatesh padmanabhan Over a year ago

I tried the following if [[ $FUNCVALUE == *$required_keyword* ]] then echo "found" else echo "no match" fi But it says no no match

John Kugelman Over a year ago

In your question, $required_keyword is 0_Menu/BAA_Record but $FUNCVALUE contains 0_Menu__47__BAA_Record with the slash / replaced by __47__. Is that the problem?

venkatesh padmanabhan Over a year ago

Not only that but also it doesnt contain the 0_Menu` I just tried to grep the output and save it a file as echo " > FUNCVALUE: $FUNCVALUE" > func.xml and manually add /0_Menu/BAA_Record It works fine, now. How can I make it work without doing any alterations such as I made now...?

tvm · Accepted Answer · 2014-09-18 13:32:58Z

0

Not sure if I understand what you want, but if you need to find out if there's part of string "a" present in variable "b" you can use simply just grep.

grep -q "a" <<< "$b"

[[ "$?" -eq 0 ]] && echo "Found" || echo "Not found"

EDIT: To clarify, grep searches for string a in variable b and returns exit status (see man grep, hence the -q switch). After that you can check for exit status and do whatever you want (either with my example or with regular if statement).

answered Sep 18, 2014 at 13:32

tvm

3,45929 silver badges39 bronze badges

5 Comments

venkatesh padmanabhan Over a year ago

I tried grep -q "$required_keyword" <<< "$FUNCVALUE" with an echo as mentioned [[ "$?" -eq 0 ]] && echo "Found" || echo "Not found" but I get the result as not found. Though as mentioned **BAA_Record ** is common in both of the output

tvm Over a year ago

Yeah, after that you need to check for exit status, variable "?" will contain either zero or one. If it contains zero, the string was found, if it contains one, nothing was found. Consult "man grep".

tvm Over a year ago

Then it wasn't found. Can you post the strings and the related actual part of the script ?

venkatesh padmanabhan Over a year ago

Hi, I have edited my original question, I hope it more clearer. The script I execute is echo -e " > Required_keyword: $required_keyword" send_func GUI WhereAmI echo -e " > FUNCVALUE: $FUNCVALUE"

venkatesh padmanabhan Over a year ago

The output echo is

> Required_keyword: 0_Menu/BAA_Record    > FUNCVALUE:  Trying to connect to 169.254.98.226 ... OK!   Executing sendFunc GUI WhereAmI  Sent Function WhereAmI [OK] PageName: "_0_Menu__47__BAA_Record"

Collectives™ on Stack Overflow

Finding a part of a string in another string variable in bash

2 Answers 2

3 Comments

5 Comments

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

5 Comments

Related