Passing multiple variables from python script to shell script

问题

I am trying to run a shell script from python by exporting the python variable to the shell script instead of directly reading them from the user. A question regarding passing array values as variable to shell script was answered successfully earlier and helped me to pass the values in an array as a input variable to the shell script. I want to export multiple variables such as FLUID, TTYPE and FLIBRARY from the following python script:

FLUID="MDM"
TTYPE=0
FLIBRARY="RefProp"
HSPACE=[0.01, 0.009, 0.008, 0.007]
subprocess.call(['./testfile1'] + [str(n) for n in HSPACE])

to the following shell script named testfile1:

#!/bin/bash
echo "$FLUID, $FLIBRARY" | ./vls.exe
for i; do
awk 'NR==8 {$1="     " a }1'  a=$i  spacingcontrol.vls > tmp.vls && mv tmp.vls spacingcontrol.vls 
awk 'NR==8 {$2="  " b "      "}1'     b=$i spacingcontrol.vls > tmp.vls && mv tmp.vls spacingcontrol.vls 
done

回答1:

You could set them as environment variables within the Python script:

import os 
import subprocess

os.environ['FLUID'] ="MDM"
os.environ['TTYPE'] = str(0)
os.environ['FLIBRARY'] = "RefProp"
HSPACE=[0.01, 0.009, 0.008, 0.007]
subprocess.call(['./testfile1'] + [str(n) for n in HSPACE])

回答2:

Is it an option for you to pass the variables as parameters?

subprocess.call(['./testfile1 %s %s' % (FLUID, FLIBRARY)] + [str(n) for n in HSPACE])

and in the bash script

#!/bin/bash
FLUID=$1
FLIBRARY=$2
echo "$FLUID, $FLIBRARY" | ./vls.exe

回答3:

Through the environment

#!/usr/bin/env python
import subprocess

FLUID="MDM"
TTYPE=0
FLIBRARY="RefProp"
HSPACE=[0.01, 0.009, 0.008, 0.007]
subprocess.call(['./testfile1'] + [str(n) for n in HSPACE],
  env={'fluid': FLUID, 'ttype': str(TTYPE), 'flibrary': FLIBRARY})

...thereafter, in shell:

#!/bin/bash
hspace=( "$@" )
declare -p fluid ttype flibrary hspace # print values

...output being:

declare -x fluid="MDM"
declare -x ttype="0"
declare -x flibrary="RefProp"
declare -a hspace='([0]="0.01" [1]="0.009" [2]="0.008" [3]="0.007")'

On the command line

Another approach is to use positional arguments.

#!/usr/bin/env python
import subprocess

FLUID="MDM"
TTYPE=0
FLIBRARY="RefProp"
HSPACE=[0.01, 0.009, 0.008, 0.007]

subprocess.call(['./testfile1', str(FLUID), str(TTYPE), str(FLIBRARY)] + [str(n) for n in HSPACE])

...and, in shell:

#!/bin/bash
fluid=$1; shift
ttype=$2; shift
flibrary=$3; shift
hspace=( "$@" )
declare -p fluid ttype flibrary hspace # print values

...output being:

declare -- fluid="MDM"
declare -- ttype="RefProp"
declare -- flibrary="0.009"
declare -a hspace='([0]="0.01" [1]="0.009" [2]="0.008" [3]="0.007")'

Note:

Use of awk -v var="$val" is the correct way to pass variable values from bash to awk; other approaches risk code injection vulnerabilities.
Use of lower-case names for user-defined environment variables is compliant with POSIX convention to avoid namespace collisions; see relevant spec.

来源：https://stackoverflow.com/questions/37449327/passing-multiple-variables-from-python-script-to-shell-script

标签

python

shell

variables