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File Descriptor redirection and duplication

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# 8  
Old 03-03-2010
Quote:
Can i know the difference between [N]<&WORD and [N]>&WORD using graph
What do you mean?
# 9  
Old 03-03-2010
they have mentioned in bash man page, Redirection section that:


Quote:
[N]<&WORD
is used to duplicate input file descriptors.

[N]>&WORD
is used similarly to duplicate output file descriptors
for example 4<&1, 4>&1, 1>&4, 1<&4, 0>&4, 0<&4, 4>&0, 4<&0

how can we apply the above operators and what is the effect.
# 10  
Old 03-07-2010
Any answer guys? if clarification is required please let me know

---------- Post updated at 10:08 AM ---------- Previous update was at 09:58 AM ----------

again i can say it in other words:

i need to know what is the difference between
Quote:
[N]<&WORD
is used to duplicate input file descriptors.

[N]>&WORD
is used similarly to duplicate output file descriptors
for example, if we apply the below direction to the shell by executing them with exec, what is the effect:
4<&1
4>&1
1>&4
1<&4
0>&4
0<&4
4>&0
4<&0
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