Shell Programming and Scripting

Just with awk:

Code:

 echo ABCA341 | awk '{
  for(i=0;i<=255;i++){A[sprintf("%c", i + 0)]=i;}
}
{
  split($1,B,"")
  for(i=1;i<=length(B);++i){
     if(B[i]<=9){
       printf("%02d",B[i])
     }
     else{
       printf("%i",A[B[i]])
     }
  }
}'
65666765030401

Regards.

Hi,
@blastit.fr : perl solution already proposed but it isn't possible to use (read post#12).

Otherwise, another way in pure builtins bash:

Code:

$ X=ABCD234;i=0;while ((i<${#X})); do [[ "${X:$i:1}" =~ [0-9] ]] || Y=\';printf "%02d" "${Y}${X:((i++)):1}";Y=""; done
65666768020304

or

Code:

echo -n ABCDE123 | while read -n 1 -d "" X ; do [[ $X =~ [0-9] ]] || Y=\';printf "%02d" "${Y}${X}";Y=""; done
6566676869010203

Regards.

Brilliant. Where can I learn more about this trick printing "'A"?

Hi RudiC,
This trick (not just in bash) validate (in : printf ) :
Regards.

Thanks for the reference. Even though it works as specified, it is not mentioned in the respective linux man page (although it is in FreeBSD).

It seems that some Linux developers update code to meet some POSIX requirements without taking the time to update the corresponding man page. (Do not read this as a slur against Linux; it happens in other development organizations too.)

It is a requirement in the POSIX description of the printf utility (although it is not allowed in the printf() family of C functions). From the 2016 edition (published by IEEE and The Open Group last week; still being balloted by ISO) of the POSIX standard printf utility EXTENDED DESCRIPTION section on P3114, L101141-104149:
The "otherwise" marked in red in the quote includes at least the d, o, and x conversion specifiers. And the bullet point marked in red is the requirement disedorgue's code relied upon. The requirement has been there since 1992, but in early versions of the standard, it was ambiguous as to whether or not the bullet point in red also applied to the floating-point conversion specifiers.