awk: Eliminating white space while setting variable

Shell Programming and Scripting
1

Hi,

I have a large flat file from host without delimiter. I'm transforming this file to a csv file using statements like

# Row 03: Customer / field position  3059 +20 
WOFABNAM=substr( $0, 3059, 20 );

and deleting the trailing whitespaces before and after with that

sub( /^ +/, "", WOFABNAM );
sub( / +$/, "", WOFABNAM );

Is here a better way to do that like pseudo

WOFABNAM=substr( $0, 3059, 20 ) | sed 's/ //g' ;

thanks in advance

Celal

2

Hi,

Removing leading and trailing spaces?

Try:

WOFABNAM=substr( $0, 3059, 20 ) | sed 's/^ *// ; s/ *$//' ;

Regards,
Birei

3 
gsub(/ /, "", WOFABNAM)

The above will remove any space in the string (not only leading/trailing).
Is that OK?

4

Thanks, that works.

I wonder (and that was the reason for my post) that the same gsub command I tried before didn't work.

It's sad that following doesn't work:

WOFABNAM=gsub(/ /, "", substr( $0, 3059, 20 ) );


nawk: syntax error at source line 18
 context is
        OFABNAM=gsub(/ /, "", >>>  substr <<< ( $0, 3059, 20 ) );
nawk: illegal statement at source line 18

thanks again,
celal

5

In your case it doesn't work because gsub third parameter is not a changeable object.

However, this won't work with a static string either, because sub and gsub do not return the modified string, they rather return the number of substitutions made.

The GNU awk's gensub returns the modified string.