Variable that is varying itself processing [duplicate]

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This question already has an answer here:

creating variable using variable value as part of new variable name

4 answers

i want to write a shell script

cd /dev
for hdd in sd*; do
 [ -f "$hdd" ] || continue
 status_$hdd=$(my_def_get_hddstaus "$hdd") #my_def_get_hddstaus returns OK or FAIL randomly just to test 
done

i get error like

status_sda0=OK: command not found
status_sda1=FAIL: command not found

I want to record the value OK or Fail into these variable, I am using bash,
what I am doing wrong.

if I write status_sda0=OK in shell it record OK into status_sda0

edited Oct 29 '17 at 12:04

asked Oct 29 '17 at 11:57

user2642486

103

marked as duplicate by don_crissti, Jeff Schaller, GAD3R, Stephen Rauch, Romeo Ninov Oct 29 '17 at 18:32

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

add a commentÂ |Â

up vote
0
down vote

favorite

This question already has an answer here:

creating variable using variable value as part of new variable name

4 answers

i want to write a shell script

cd /dev
for hdd in sd*; do
 [ -f "$hdd" ] || continue
 status_$hdd=$(my_def_get_hddstaus "$hdd") #my_def_get_hddstaus returns OK or FAIL randomly just to test 
done

i get error like

status_sda0=OK: command not found
status_sda1=FAIL: command not found

I want to record the value OK or Fail into these variable, I am using bash,
what I am doing wrong.

if I write status_sda0=OK in shell it record OK into status_sda0

edited Oct 29 '17 at 12:04

asked Oct 29 '17 at 11:57

user2642486

103

marked as duplicate by don_crissti, Jeff Schaller, GAD3R, Stephen Rauch, Romeo Ninov Oct 29 '17 at 18:32

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

add a commentÂ |Â

up vote
0
down vote

favorite

This question already has an answer here:

creating variable using variable value as part of new variable name

4 answers

i want to write a shell script

cd /dev
for hdd in sd*; do
 [ -f "$hdd" ] || continue
 status_$hdd=$(my_def_get_hddstaus "$hdd") #my_def_get_hddstaus returns OK or FAIL randomly just to test 
done

i get error like

status_sda0=OK: command not found
status_sda1=FAIL: command not found

I want to record the value OK or Fail into these variable, I am using bash,
what I am doing wrong.

if I write status_sda0=OK in shell it record OK into status_sda0

edited Oct 29 '17 at 12:04

asked Oct 29 '17 at 11:57

user2642486

103

This question already has an answer here:

creating variable using variable value as part of new variable name

4 answers

i want to write a shell script

cd /dev
for hdd in sd*; do
 [ -f "$hdd" ] || continue
 status_$hdd=$(my_def_get_hddstaus "$hdd") #my_def_get_hddstaus returns OK or FAIL randomly just to test 
done

i get error like

status_sda0=OK: command not found
status_sda1=FAIL: command not found

I want to record the value OK or Fail into these variable, I am using bash,
what I am doing wrong.

if I write status_sda0=OK in shell it record OK into status_sda0

This question already has an answer here:

creating variable using variable value as part of new variable name

4 answers

edited Oct 29 '17 at 12:04

asked Oct 29 '17 at 11:57

user2642486

103

edited Oct 29 '17 at 12:04

asked Oct 29 '17 at 11:57

user2642486

103

asked Oct 29 '17 at 11:57

user2642486

103

asked Oct 29 '17 at 11:57

user2642486

103

marked as duplicate by don_crissti, Jeff Schaller, GAD3R, Stephen Rauch, Romeo Ninov Oct 29 '17 at 18:32

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

marked as duplicate by don_crissti, Jeff Schaller, GAD3R, Stephen Rauch, Romeo Ninov Oct 29 '17 at 18:32

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

add a commentÂ |Â

1 Answer
1

active

oldest

votes

up vote
0
down vote

accepted

If the variable name is not a static string (or rather: If the part before the = contains anything not allowed in a variable name) then the assignment is not recognized as such.

You need eval:

tmp_var="$(my_def_get_hddstaus "$hdd")"
eval status_$hdd=""$tmp_var""

edit

You can echo the value using eval again or using indirection:

eval echo "$status_$hdd"

var_name="status_$hdd"
echo "$!var_name"

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

add a commentÂ |Â

1 Answer
1

active

oldest

votes

1 Answer
1

active

oldest

votes

up vote
0
down vote

accepted

If the variable name is not a static string (or rather: If the part before the = contains anything not allowed in a variable name) then the assignment is not recognized as such.

You need eval:

tmp_var="$(my_def_get_hddstaus "$hdd")"
eval status_$hdd=""$tmp_var""

edit

You can echo the value using eval again or using indirection:

eval echo "$status_$hdd"

var_name="status_$hdd"
echo "$!var_name"

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

add a commentÂ |Â

up vote
0
down vote

accepted

If the variable name is not a static string (or rather: If the part before the = contains anything not allowed in a variable name) then the assignment is not recognized as such.

You need eval:

tmp_var="$(my_def_get_hddstaus "$hdd")"
eval status_$hdd=""$tmp_var""

edit

You can echo the value using eval again or using indirection:

eval echo "$status_$hdd"

var_name="status_$hdd"
echo "$!var_name"

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

add a commentÂ |Â

up vote
0
down vote

accepted

If the variable name is not a static string (or rather: If the part before the = contains anything not allowed in a variable name) then the assignment is not recognized as such.

You need eval:

tmp_var="$(my_def_get_hddstaus "$hdd")"
eval status_$hdd=""$tmp_var""

edit

You can echo the value using eval again or using indirection:

eval echo "$status_$hdd"

var_name="status_$hdd"
echo "$!var_name"

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

If the variable name is not a static string (or rather: If the part before the = contains anything not allowed in a variable name) then the assignment is not recognized as such.

You need eval:

tmp_var="$(my_def_get_hddstaus "$hdd")"
eval status_$hdd=""$tmp_var""

edit

You can echo the value using eval again or using indirection:

eval echo "$status_$hdd"

var_name="status_$hdd"
echo "$!var_name"

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

edited Oct 29 '17 at 13:46

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

answered Oct 29 '17 at 12:14

Hauke Laging

53.6k1282130

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

add a commentÂ |Â

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

but now how would echo the value of variable dynamically $(status_$hdd). This is not working, Thanks for above solution atleast.
â€“Â user2642486
Oct 29 '17 at 13:37

@user2642486 See my edit
â€“Â Hauke Laging
Oct 29 '17 at 13:46

unix.stackexchange.com/questions/98419/â€¦ I found in reference too eval "echo "$filemsg$word1"" Thanks again
â€“Â user2642486
Oct 29 '17 at 13:49

add a commentÂ |Â

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