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Возможно ли, чтобы bash / ksh вызывал переменную переменной, например:

 set -A MY_ARRAY ${${var}_something}
  

BR
Колесар

В bash:

 VAR1=aap
VAR2=noot

USEVARNAME=VAR2
echo ${!USEVARNAME}

USEVARNAME=VAR1
echo ${!USEVARNAME}
  

С принтами

 noot
aap
  

Вы, вероятно, ссылаетесь на косвенные ссылки: http://tldp.org/LDP/abs/html/ivr.html

 # Indirect reference.
eval a=$$a
  

Весь фрагмент кода с этого сайта:

 #!/bin/bash
# ind-ref.sh: Indirect variable referencing.
# Accessing the contents of the contents of a variable.

# First, let's fool around a little.

var=23

echo "$var   = $var"           # $var   = 23
# So far, everything as expected. But ...

echo "$$var  = $$var"         # $$var  = 4570var
#  Not useful ...
#  $$ expanded to PID of the script
#  -- refer to the entry on the $$ variable --
#  and "var" is echoed as plain text.
#  (Thank you, Jakob Bohm, for pointing this out.)

echo "\$$var = $$var"       # $$var = $23
#  As expected. The first $ is escaped and pasted on to
#  the value of var ($var = 23 ).
#  Meaningful, but still not useful. 

# Now, let's start over and do it the right way.

# ============================================== #


a=letter_of_alphabet   # Variable "a" holds the name of another variable.
letter_of_alphabet=z

echo

# Direct reference.
echo "a = $a"          # a = letter_of_alphabet

# Indirect reference.
  eval a=$$a
# ^^^        Forcing an eval(uation), and ...
#        ^   Escaping the first $ ...
# ------------------------------------------------------------------------
# The 'eval' forces an update of $a, sets it to the updated value of $$a.
# So, we see why 'eval' so often shows up in indirect reference notation.
# ------------------------------------------------------------------------
  echo "Now a = $a"    # Now a = z

echo

# Now, let's try changing the second-order reference.

t=table_cell_3
table_cell_3=24
echo ""table_cell_3" = $table_cell_3"            # "table_cell_3" = 24
echo -n "dereferenced "t" = "; eval echo $$t    # dereferenced "t" = 24
# In this simple case, the following also works (why?).
#         eval t=$$t; echo ""t" = $t"

echo

t=table_cell_3
NEW_VAL=387
table_cell_3=$NEW_VAL
echo "Changing value of "table_cell_3" to $NEW_VAL."
echo ""table_cell_3" now $table_cell_3"
echo -n "dereferenced "t" now "; eval echo $$t
# "eval" takes the two arguments "echo" and "$$t" (set equal to $table_cell_3)