bash evironment variables starting from a digit

Question

I want to set an environment variable in bash, which starts from a digit. The environment of the process can contain such variables (it just doesn't care). But in the shell you have to create the variables, and then export them so they go to the environment. Is there a way to put some value into shell's environment without touching variables, or maybe create a variable that starts with a digit?

Answer 1

The only valid beginning character types for bash variables are letters and underscores.

Answer 2

Why do you want to do this? You can do:

export _1="some value"

or

export a1="some value"

The reason that you can't do what you're asking is that a variable like "$1" would be confused with the positional parameter $1.

Answer 3

The only way I could think of was by starting a new shell using env:

env 0FOO=BAR /usr/bin/bash

I tried this under Cygwin and it seemed to work.

Answer 4

The processing required is fiddly and tedious and not dreadfully sensible, but (in outline, error checks on malloc() omitted):

char **env = environ;
while (*env != 0)
    *env++;
char **newenv = malloc((env - environ + 1) * sizeof(*newenv));
memcpy(newenv, environ, (env - environ) * sizeof(char *));
newenv[env - environ] = "386=pygmalion";
newenv[env - environ + 1] = 0;
char *args[] = { "modded-env-bash", 0 };
execve("/bin/bash", args, newenv);
exit(1);