如何在系统命令中使用awk脚本的shell变量？

Question

I am troubleing in coverting hex to decimal from txt file using awk.

I want to do like this

awk -F' '   '{   system("echo '$((16#"$1"))'") '} $file_name

but not work... then I try other code

awk -F' ' -v var="\"echo \x27\$((16#" '{var=var$1"))\x27\"" system(var) }' $file_name

also not work. but print var then enter image description here

what should i do?

Answer 1

Using awk

To use GNU awk to convert hex to decimal:

$ echo '0xFFFFFFFE' | awk -n '{printf "%i\n",$1}'
4294967294

Or:

$ x='0xFFFFFFFE'
$ awk -n -v x="$x"  'BEGIN{printf "%i\n",x}'
4294967294

Or:

$ x='0xFFFFFFFE'; awk -v x="$x"  'BEGIN{print strtonum(x)}'
4294967294

To convert hex to decimal using bash:

$ echo $((0xFFFFFFFE))
4294967294

Limitations:

1. GNU awk is limited to 52-bit integers.

2. The above could be extended to perform two's-complement arithmetic but it hasn't.

To avoid both these limitations, see the python solution below:

Using python

Awk does not handle long integers. For long integers, consider this python script:

$ cat n.py
#!/usr/bin/python3
import sys
def h(x):
        x = int(x, 16)
        return x if x < 2**63 else x - 2**64

for line in sys.stdin:
        print(*[h(x) for x in line.split()])

Let's use this input file:

$ cat file
FFFFFFFFFFFFFFFF EFEFEFEFEFEFEFEF

When we run our script, we find:

$ python3 n.py <file
-1 -1157442765409226769