Help with exec command and file descriptors II


 
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# 1  
Old 03-18-2008
Help with exec command and file descriptors II

Need to close files which descriptor number are larger than 9 in ksh.
'exec 10>&-' fails with 'ksh: 10: not found'. How do you specify file descriptors which occupies two or more digits in ksh script?
Thanks,
Masaki
# 2  
Old 03-18-2008
You can't do that. ksh can only control 0 through 9 directly.
# 3  
Old 01-03-2009
At ksh, I can only close fd to 9 as your case.
But, I can do it by using Perl as the following test case.
t1.c : open 10 files
t2.pl : close fd from 3
t3.c : only wait a key to verify fds by using AIX 5.3 dbx's fd subcomamnd.

At p2.pl
use POSIX::close

for ($fd=100; $fd > 2; $fd--) { # 100 is ok on my case.
POSIX::close($fd) # execution error, but has effect.
}

exec "./t3"
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