parsing output from nm command with awk - Linux Bash

Question

I working on some code optimization and I would to inspect the size of my functions instead to read huge disassembly file. After compilation on Debug, I use the nm command to read the .o. We got this :

nm --size-sort $OBJFILEPATH.o



000000000000000b r __PRETTY_FUNCTION__.6473

0000000000000017 t extract_h

0000000000000036 t L_mult

000000000000003a t sature32

0000000000000042 t L_mac

0000000000000048 t L_add

000000000000005c t Mac16x11

0000000000000077 t L_shl

0000000000000083 t L_shr

00000000000000df T G729Convolve

0000000000000114 T G729Residu

00000000000001bc T G729Syn_filt_L_H

00000000000001bc T G729Syn_filt_L_SUBFR

Now, into a bash script I would like to parse only the 1st column wich each line represent a single array element in bash.

My command will be :

read FUNCSIZE <<< $(nm --size-sort $OBJFILEPATH.o | awk '{print $1}')

And for make sure that everything is ok I check the size of my FUNCSIZE array.

SIZE=${#FUNCSIZE[@]}

echo size is $SIZE

for s in $FUNCSIZE

do

    echo $s

done

I got this as output:

size is 1

000000000000000b

0000000000000017

0000000000000036

000000000000003a

0000000000000042

0000000000000048

000000000000005c

0000000000000077

0000000000000083

00000000000000df

0000000000000114

00000000000001bc

00000000000001bc

Why size is '1' and why I'm able to print each element like it was inside an array. It's seem that the output still have a 'space' ' ' at the end of the line. Is there any RegEx with awk that will avoid to include the separator field into the array?

Thank for your help !!

EDIT AFTER ANSWER

read -a FUNCSIZE <<< $(nm --size-sort $OBJFILEPATH.o | awk '{print $1}')

SIZE=${#FUNCSIZE[*]}

for((i=0; i<SIZE; i++))

do

    echo ${FUNCSIZE[$i]}

done

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Answer 1

The way you wrote it, FUNCSIZE is not an array, but a regular variable.

Add the -a flag for read:

read -a FUNCSIZE <<< $(nm --size-sort $OBJFILEPATH.o | awk '{print $1}')

Note that using all-uppercase names for user-defined variables is not recommended, to avoid conflicts (and confusion) with environmental variables and special shell variables.

(Thanks @mklement0 for the tips and links!)

parsing output from nm command with awk - Linux Bash

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