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ksh vs perl strange interaction.

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# 8  
Old 01-10-2011
Do a "stty -a". Isn't a cntl-D your eof character? eof means "end of file". You are not supposed to continue reading after eof. You could try to reopen the terminal with "exec < /dev/tty".
# 9  
Old 01-10-2011
I believe that something else is going on. Using ksh93, I do not need to enter Ctrl-D twice on any platform and read works exactly as documented.

If you spell out your exact requirements, we can probably solve your problem for you in a simple manner. Are you logged in at the console or on some remote terminal/terminal emulator?
# 10  
Old 01-10-2011
Quote:
Originally Posted by Perderabo
Do a "stty -a";. Isn't a cntl-D your eof character? eof means &quot;end of file&quot;. You are not supposed to continue reading after eof. You could try to reopen the terminal with ";exec < /dev/tty";.
Hello, I tried you suggestion. Doesn't work either. Anyway, this code requires 2 x Ctrl-D, the first time:

Code:
echo a|read a
read line

No Ctrl-D read in the first read.

---------- Post updated at 07:18 PM ---------- Previous update was at 07:14 PM ----------

Quote:
Originally Posted by fpmurphy
I believe that something else is going on. Using ksh93, I do not need to enter Ctrl-D twice on any platform and read works exactly as documented.

If you spell out your exact requirements, we can probably solve your problem for you in a simple manner. Are you logged in at the console or on some remote terminal/terminal emulator?
Indeed, Ctrl-D is the EOF, as shown in stty -a

However, this doesn't work either, where no Ctrl-D is involved in the first line.

Code:
 echo "a"|read a
 readline

Adding exec < /dev/tty between the two statements doesn't help.

I'm using Konsole in Fedora/KDE. Tried with another terminal. Same result.

Code:
 [root@BE01850T400 ~]# rpm -qf $(which konsole)
 kdebase-4.4.5-1.fc12.i686

Last edited by jlovi; 01-10-2011 at 02:02 PM..
# 11  
Old 01-10-2011
Jlovi, you started off with a purported problem with ksh93 on AIX. Now you are talking about Konsole on Fedora/KDE using readline. What exactly are you trying to achieve, under what shell and on what platform? You need to spell it out for us!
# 12  
Old 01-10-2011
Quote:
Originally Posted by fpmurphy
Jlovi, you started off with a purported problem with ksh93 on AIX. Now you are talking about Konsole on Fedora/KDE using readline. What exactly are you trying to achieve, under what shell and on what platform? You need to spell it out for us!
My stations is a Fedora/KDE system, I use Konsole in order to connect to an AIX server, using ssh. The script runs on the AIX server. You were talking of terminal issues, that's why I mentionned my workstation. And "read line" is in two words Smilie.

However, I'm a bit skeptical about a terminal issue since it works in ksh88, but not in ksh93. Looks like a specific bug or feature. IMHO, ksh93 is not as stable as ksh88, as I get something coredumps in ksh93 for things that work in ksh88.

Currenly my script works perfectly in ksh88 but I have experimental code that requires ksh93 (for keybinding), that's why I'd like to make it work with this latest version of ksh.
Last edited by jlovi; 01-10-2011 at 03:24 PM..
# 13  
Old 01-10-2011
Quote:
Originally Posted by jlovi
Got something like this:

Code:
#!/usr/bin/ksh93
line=$(trap 'line=""' INT;head -1|(set -f;read -r line;print -r "$?:$line") 2> /dev/null)
[ "X$line" != "X" ] && read_res=$(print -r "$line"|cut -f1 -d:)
line=$(print -r "$line"|cut -f2- -d:)

Tested successfully on Linux (Fedora) and AIX

Works in ksh. Core dump in ksh93! Smilie
Your script works fine and no Core dump in AIX 5.3:
Code:
$ oslevel -s
5300-10-00-0000
$ what /bin/ksh93 | grep Version
        Version M-12/28/93e
$ cksum /bin/ksh93
1875805810 791843 /bin/ksh93

# 14  
Old 01-11-2011
Quote:
Originally Posted by Chubler_XL
Your script works fine and no Core dump in AIX 5.3:
Code:
$ oslevel -s
5300-10-00-0000
$ what /bin/ksh93 | grep Version
        Version M-12/28/93e
$ cksum /bin/ksh93
1875805810 791843 /bin/ksh93

Did you try to type Ctrl-C?
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