how to export integer value to the environment variable in c -


i have tried below program export value environment variable. want export integer value environment variable. below program taking value "a" instead of 1. how export integer value environment variable. 

#include<stdio.h>  void chnge_env_var(int a) {     char *name1="env_var";     char *val=null;     int status;     status = putenv("env_var=a");     printf("status %d\n",status);     val = getenv(name1);     printf("val %s\n",val); }  int main() {     int a=1;     chnge_env_var(a); return 0; }

the environment can hold string values. store integer have convert string , store that. when reading can convert string integer.

int = 10; char env_var[20]; // length of 'env_var=' plus 12 sprintf(env_var, "env_var=%d", a); putenv(env_var);

as 'code clown' pointed out, snprintf might used instead if aren't absolutely sure buffer of right size:

snprintf(env_var, 20, "env_var=%d", a);

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