linux - Awk: Cannot concatenate strings -

i'm dealing awk, , have 3 variables work with:

• $0 variable - example it's equivalent to:

path/filename.cpp log_err << "error in log" << e.what();

• $logname variable - parsed out name of cpp file, namely:

filename

• $2 variable - contains default second value:

log_err

question:

what i'm trying concatenate values so:

logname=$logname $2;

but instead of expected value filenamelog_err, this:

filename log_err << "error in log" << e.what();

what doing wrong?

edit: awk code requested:

awk '{ logname=sub(/^.*\//,"",$1); logname=sub(/\..*:/,"",$logname);  print $logname; print $2;  logname=$logname $2;  print $logname; }' $file 

edit2: fixed. never call on $ variables in awk unless it's field number. :)

awk '{ logname=$1; sub(/^.*\//,"",logname); sub(/\..*:/,"",logname); print logname; logname=logname $2; print logname; }' $file 

logname=$logname $2; 

this code wrong.

you used $logname, means column index logname, not want.

if value of logname string filename, awk try column $filename here, if variable not defined/assigned, , try number, awk 0. can test this:

kent$ echo "xxxx y y"|awk '{print $foo}' xxxx y y 

so guess, fix be: (if logname set right value, said)

logname=logname $2; 

edit

you should never call $logname check example:

kent$echo "111 222"|awk -v logname="filename" '{logname=logname $2;print logname}'                                                                              filename222