Shell Programming and Scripting

I am trying to escape single quote in awk, but could not:

Code:

awk ' BEGIN{ fstr="COMPRESS('Y','N')" } 
{
substr($1,len-3,4)~/_IND/
len=length($1)
if(substr($1,len-3,4)~/_IND/)
  printf("%-32s%-14s%-5s%-14s\n",$1,$2,$3,$fstr,$4,$5,$6,$7)
}
' tt.txt > out.log

Error:

Code:

awk: Field $(COMPRESS(Y,N)) is not correct.
 The input line number is 1. The file is tt.txt.
 The source line number is 6.

Code:

awk ' BEGIN{ fstr="'"COMPRESS('Y','N')"'" }

Still getting error !

awk: Field $(COMPRESS('Y','N')) is not correct.
The input line number is 1. The file is tt.txt.
The source line number is 6.

Which shell are you using? What is the version of awk? My bash (version 4.1.2) and awk (version GNU Awk 3.1.7) work smooth without spilling out errors.

New to unix so if need the commands to check the shell and awk version

Try this... single double single Y single double single

Code:

awk 'BEGIN{ fstr="COMPRESS('"'Y'"','"'N'"')" }'

--ahamed

---------- Post updated at 08:33 PM ---------- Previous update was at 08:31 PM ----------

Code:

awk --version

bash --version

--ahamed

Typically the command awk --version will generate the version of awk that you are using. If you are running on Solaris, it's wise to use nawk instead as the default awk in that environment is quite old and has lots of limitations.

The command uname -a will generate information about the OS you are running and the version.

Running echo $SHELL at the command prompt should give you the name of the shell you are using. To get the version you might might trying running the shell name with --version on the command line; modern versions of Korn shell and bash support this.

As for your problem...
What is generating the error message is in your printf() statement. You do not need the dollar sign in front of the variable name fstr. Past that, the bit of quoting that was suggested should work.

I'm not a fan of opening and closing quotes in the middle of an awk programme as that leads to maintenance problems. If it is just one string that you need to have single quotes appear in you could try this:

Code:

awk -v fstr="COMPRESS('Y','N')" '
{
    substr($1,len-3,4)~/_IND/
    len=length($1)
    if(substr($1,len-3,4)~/_IND/)
       printf("%-32s%-14s%-5s%-14s\n",$1,$2,$3, fstr, $4,$5,$6,$7)
 }
 ' tt.txt > out.log

Supplying the variable on the awk command, outside of the programme, allows you to use the single quotes within the double quotes, and it's easier to read (IMHO).