Is there a way to determine the ascii value of a character? For example, let's say a shell variable has the value 'A'. I would like it's ascii value (e.g. 65 in this case). I would like to do this from a script (preferably ksh).

I just stumbled upon the following...

$ printf "%d" "'A"

This will give me 65, so likewise I can certainly do this...

$ var=A
$ printf "%d" "'${var}"

What I don't understand is the single quote immediately preceding the character. This is the only way it'll work, but I've never seen that syntax before. I quickly glanced at the man pages for printf and I still don't fully understand this. Can someone please explain? Thank you.

Single quotes like 'A' around a character is the convention used in the C language to distinguish a character from a string of characters like "A" which is enclosed in double quotes. That's all there is to it.

This is not a "pair" of single quotes. It's simply a single quote (by itself) preceding the character (i.e. 'A) . That's what I've never seen before. In fact, if you use a pair of single quotes, the conversion to the ascii value does not work.

Interesting. From info printf...

Both of these seem to answer my question. None of the man pages (on Solaris 10) explained this with this kind of detail. Thank you.

This is slightly off topic, but may give a clue:


I use a report generation program (CyberQuery). One option is to output the report as an Excel document.

Within Excel, if any cell of the document is all digits, but the source field was Aplha format, the data is preceeded by a single quote.

On the spreadsheet you see the data, including leading zeros (if any), but you do not see the leading quote.

Only when you select one of those cells, and look up to the cell contents field, do you see the single leading quote.


Hope that helps, or at least gives you something to research / consider.