pattern matching

[sandeepmur]

Hi,

I have the fwg code :

grpName="abc"
name="SBL|ttt|abc"

echo $name | awk -v g=$grpName 'index($1,"|"g)!=0 { print "HELLO"}'

my problem is that I want to print "HELLO" only when grpName is found as it is in name variable. In the above code, if i leave out 'c' in grpName, it still prints HELLO.

any suggestions ?
thnx

 

[PHV]

This is normal behaviour:
"SBL|ttt|abc"

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

Yes, I understand that this is normal. So, how do I make sure that the string grpName is present entirely in string name ?

thnx

 

[sandeepmur]

I can probably use the split function, break up the name variable into an array, use a for loop to chk whether the var grpName exists in the array.. but this appears quite tedious..

any better alternative ?

 

[PHV]

If by chance you play with gawk you may try this:
echo $name | gawk -v g=$grpName '$1~"(^|\|)"g"(\||$)"{ print "HELLO"}'

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

I substituted gawk with just awk and it works great.. just one question:

can I put $1~"(^|\|)"g"(\||$) within an IF condition so I can have an else construct ??

I tried inserting an if condition but it gave a :

syntax error The source line is 3.
The error context is
>>> if <<< ( $4~"(^|\|)"g"(\||$)" ) { sub(/-/, "LOCKED", buf) };


thnx

 

[PHV]

The if instruction shouldn't be in the pattern section but the action, ie inside { }.

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

thnx.. I placed the if instruction inside {} but continue hv some trouble.. heres the code..

awk -v g=$grpName '
{buf=$0}
 {if($4~"(^|\|)"g"(\||$)") { then sub(/-/, "LOCKED", buf)  }
	else {
	print "HELLO" > "err.txt"
	}
};
{ print buf}

The problem is that the else construct is always being executed even if the IF condition fails.

thnx

 

[sandeepmur]

oops.. the "then" is outside the {} and the error obtained is :

syntax error The source line is 3.
The error context is
{if($4~"(^|\|)"g"(\||$)") then >>> { <<<
awk: The statement cannot be correctly parsed.
The source line is 3.
syntax error The source line is 4.

thnx

 

[PHV]

In the man awk or info gawk page pay attention to the syntax of the if statement.

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

I had already tried this:

if($4~"(^|\|)"g"(\||$)") sub(/-/, "LOCKED", buf) [ else print "helllo" > abc.txt ]

but getting the same error.

 

[PHV]

if($4~"(^|\|)"g"(\||$)") sub(/-/, "LOCKED", buf); else print "helllo" > "abc.txt"

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

problem continues..

syntax error The source line is 5.
The error context is
>>> if <<< ($4~"(^|\|)"g"(\||$)") sub(/-/, "LOCKED", buf); else print "helllo" > "abc.txt"


thnx

 

[PHV]

I showed you the correct syntax for the if ... else one-line statement.
It should, as previously stated, be inside { }.

Hope This Helps, PH.
Want to get great answers to your Tek-Tips questions? Have a look at FAQ219-2884 or FAQ181-2886

 

[sandeepmur]

Hi,

When inside the {}, it doesnt give any error but the ELSE construct gets executed again even when the if condition proves true.

 

[PHV]

Can you please post your whole actual program, samples input, expected result and actual result ?