Re: printf treats arguments of %c not as expected
Hi, I agree this is not a bug. %c works as described. However, Mr. Wang may want to read one of Greg's brilliant FAQ entries [1]. In general it's a bit of a pity that printf can do character-number conversion, but not (directly) back. But it is like it is and the workarounds are not really complicated. Jan [1] http://mywiki.wooledge.org/BashFAQ/071 -- Be conservative in what you do, be liberal in what you accept from others. - jbp, master of the net, in RFC793
Re: printf treats arguments of %c not as expected
Thanks Jan, Greg's solution is great! wyf 2011/6/23 Jan Schampera jan.schamp...@web.de: Hi, I agree this is not a bug. %c works as described. However, Mr. Wang may want to read one of Greg's brilliant FAQ entries [1]. In general it's a bit of a pity that printf can do character-number conversion, but not (directly) back. But it is like it is and the workarounds are not really complicated. Jan [1] http://mywiki.wooledge.org/BashFAQ/071 -- Be conservative in what you do, be liberal in what you accept from others. - jbp, master of the net, in RFC793
Re: printf treats arguments of %c not as expected
Yunfeng Wang wrote: Perhaps bash should clarify this issue in its documents such that users like me would not be misguided again. Since the reference to printf(3) is misleading sometimes, I made some document [1] for Bash's printf only. It's far from perfect, but at least it mentions %s and first character ;-) Jan [1] http://wiki.bash-hackers.org/commands/builtin/printf -- Be conservative in what you do, be liberal in what you accept from others. - jbp, master of the net, in RFC793
Re: printf treats arguments of %c not as expected
2011/6/23 Jan Schampera jan.schamp...@web.de: However, Mr. Wang may want to read one of Greg's brilliant FAQ entries [1]. [1] http://mywiki.wooledge.org/BashFAQ/071 On Thu, Jun 23, 2011 at 04:00:35PM +0800, Yunfeng Wang wrote: Thanks Jan, Greg's solution is great! Just for the record, I didn't write the content of BashFAQ/071. I don't know who did; the oldest wiki history entry says redondos but the wiki's history is also incomplete, since a lot of the FAQ content was transferred from heiner's older FAQ. Also, the bottom comment of the page is signed mjf; I don't know who that is, and I don't know whether that's the original content author, or someone who was simply pointing out where the quote trick is documented. The wiki is very much a group effort, as it should be.
Re: printf treats arguments of %c not as expected
Hi, Yunfeng Wang wrote: $ printf %c 65 66 67 666 The expected output is ABC, i.e. characters with ASCII code of 65 66 67 I believe the current behavior is correct. POSIX (XCU.4.printf) sayeth[*]: 11. The argument to the 'c' conversion specifier can be a string containing zero or more bytes. If it contains one or more bytes, the first byte shall be written and any additional bytes shall be ignored. If the argument is an empty string, it is unspecified whether nothing is written or a null byte is written. I would suggest using something like perl -e 'print(chr(65), chr(66), chr(67), \n);' or for i in 65 66 67 do eval printf \'\\$(printf %03o $i)\' done printf '\n' for your application. Back to the bug: I don't see any explanation of printf %c when I run man bash. Perhaps your manual is different from mine, but if you, perhaps it would be possible to suggest a few words to explain this for future readers. Thanks and regards, Jonathan [*] http://unix.org/2008edition/
