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Some oddities concerning the default bash installed on a typical macintosh computer (osX 10.6.8)

> bash --version
GNU bash, version 3.2.48(1)-release (x86_64-apple-darwin10.0)
Copyright (C) 2007 Free Software Foundation, Inc.

echo -e weirdness Something I came across today while testing some bash-4.2 scripts on a mac; to print some text in bold I used the ancient ansi escape sequence <ESC>[1m.

Now printing this to the screen should've been simply a question of doing a quick echo -e "\e[1m bold \e[0m " … even the installed 3.2 manpage said it would. It didn't though…

> echo -e "\e[1m bold \e[0m"
\e[1m bold \e[0m

WTH? I thought as I tried some other escapes ( \n \t \a ) and without problem the newline, the tab and the sysbeep/bell sounded.

Ok, I thought, maybe escape is disabled on some level.. but just out of curiosity, and a healthy dose of boredom, I tried to

 echo -e "So what if I \033[1m give the octal value of \e033[0m escape"
and Lo-and-Behold, it printed it proper.

So what if I give the octal value of escape

Now I started getting REALLY confused…. why block the one (\e) and not the other… So I tried a echo $' why dont u \e[1mW0RK\e[0m ??' and, of course, because who ever wanted consistency from their computers the ol' $'string' syntax DID give me bold.

If anyone knows which setting, flag, version or environment influence somesuch has this effect.. Please DO let me know. :)

/rant Krim – Don't even get me started about printf "%(%Y-%m-%d)T" -1 ;)

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Amer Neely, 2014/12/28 19:13

Was doing some research on OSX in general and being a bit of a geek found this post very interesting. I have a Terminal window open all the time on my iMac with a couple of different tabs active. Did some looking around and found a posting at stack overflow that might shed some light on this one: <>

Granted it is more about sed but who knows where that might lead.

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  • mac.1328840434.txt
  • Last modified: 2012/02/10 02:20
  • by drkrimson