Do math arithmetic on busybox sh

up vote
0
down vote

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I have string variables MIN and SEC (minute and seconds):

MIN="1"
SEC="34"

I want to do calculations on these:

TOTSEC = MIN*60 + SEC

I tried:

expr $SEC + $MIN * 60

Result:

expr: non-numeric argument

Let it be known I am running busybox on a custom microcomputer and so have no access to bash, bc, and that other solution provides.

edited Mar 23 at 2:09

cuonglm

97.2k21185278

asked Mar 23 at 1:57

GeneCode

658

You probably just need to escape the * i.e. expr $SEC + $MIN * 60
â€“Â steeldriver
Mar 23 at 2:12

add a commentÂ |Â

up vote
0
down vote

favorite

I have string variables MIN and SEC (minute and seconds):

MIN="1"
SEC="34"

I want to do calculations on these:

TOTSEC = MIN*60 + SEC

I tried:

expr $SEC + $MIN * 60

Result:

expr: non-numeric argument

Let it be known I am running busybox on a custom microcomputer and so have no access to bash, bc, and that other solution provides.

edited Mar 23 at 2:09

cuonglm

97.2k21185278

asked Mar 23 at 1:57

GeneCode

658

You probably just need to escape the * i.e. expr $SEC + $MIN * 60
â€“Â steeldriver
Mar 23 at 2:12

add a commentÂ |Â

up vote
0
down vote

favorite

I have string variables MIN and SEC (minute and seconds):

MIN="1"
SEC="34"

I want to do calculations on these:

TOTSEC = MIN*60 + SEC

I tried:

expr $SEC + $MIN * 60

Result:

expr: non-numeric argument

Let it be known I am running busybox on a custom microcomputer and so have no access to bash, bc, and that other solution provides.

edited Mar 23 at 2:09

cuonglm

97.2k21185278

asked Mar 23 at 1:57

GeneCode

658

I have string variables MIN and SEC (minute and seconds):

MIN="1"
SEC="34"

I want to do calculations on these:

TOTSEC = MIN*60 + SEC

I tried:

expr $SEC + $MIN * 60

Result:

expr: non-numeric argument

Let it be known I am running busybox on a custom microcomputer and so have no access to bash, bc, and that other solution provides.

edited Mar 23 at 2:09

cuonglm

97.2k21185278

asked Mar 23 at 1:57

GeneCode

658

edited Mar 23 at 2:09

cuonglm

97.2k21185278

edited Mar 23 at 2:09

cuonglm

97.2k21185278

edited Mar 23 at 2:09

cuonglm

97.2k21185278

asked Mar 23 at 1:57

GeneCode

658

asked Mar 23 at 1:57

GeneCode

658

asked Mar 23 at 1:57

GeneCode

658

You probably just need to escape the * i.e. expr $SEC + $MIN * 60
â€“Â steeldriver
Mar 23 at 2:12

add a commentÂ |Â

You probably just need to escape the * i.e. expr $SEC + $MIN * 60
â€“Â steeldriver
Mar 23 at 2:12

You probably just need to escape the * i.e. expr $SEC + $MIN * 60
â€“Â steeldriver
Mar 23 at 2:12

add a commentÂ |Â

1 Answer
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up vote
5
down vote

busybox uses ash, so you can use:

MIN=1 SEC=34 busybox sh -c 'echo "$(( MIN*60 + SEC ))"'
94

Or with expr:

MIN=1 SEC=34 busybox sh -c 'expr " $MIN" * 60 + "$SEC"'
94

answered Mar 23 at 2:12

cuonglm

97.2k21185278

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

add a commentÂ |Â

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active

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1 Answer
1

active

oldest

votes

up vote
5
down vote

busybox uses ash, so you can use:

MIN=1 SEC=34 busybox sh -c 'echo "$(( MIN*60 + SEC ))"'
94

Or with expr:

MIN=1 SEC=34 busybox sh -c 'expr " $MIN" * 60 + "$SEC"'
94

answered Mar 23 at 2:12

cuonglm

97.2k21185278

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

add a commentÂ |Â

up vote
5
down vote

busybox uses ash, so you can use:

MIN=1 SEC=34 busybox sh -c 'echo "$(( MIN*60 + SEC ))"'
94

Or with expr:

MIN=1 SEC=34 busybox sh -c 'expr " $MIN" * 60 + "$SEC"'
94

answered Mar 23 at 2:12

cuonglm

97.2k21185278

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

add a commentÂ |Â

up vote
5
down vote

busybox uses ash, so you can use:

MIN=1 SEC=34 busybox sh -c 'echo "$(( MIN*60 + SEC ))"'
94

Or with expr:

MIN=1 SEC=34 busybox sh -c 'expr " $MIN" * 60 + "$SEC"'
94

answered Mar 23 at 2:12

cuonglm

97.2k21185278

busybox uses ash, so you can use:

MIN=1 SEC=34 busybox sh -c 'echo "$(( MIN*60 + SEC ))"'
94

Or with expr:

MIN=1 SEC=34 busybox sh -c 'expr " $MIN" * 60 + "$SEC"'
94

answered Mar 23 at 2:12

cuonglm

97.2k21185278

answered Mar 23 at 2:12

cuonglm

97.2k21185278

answered Mar 23 at 2:12

cuonglm

97.2k21185278

answered Mar 23 at 2:12

cuonglm

97.2k21185278

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

add a commentÂ |Â

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

Appreciate your answer. But I ended up using awk. TOTSEC=`awk "BEGIN print $SEC+($MIN*60)"`
â€“Â GeneCode
Mar 23 at 2:50

add a commentÂ |Â

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