Function: getenv-internal

getenv-internal is a function defined in callproc.c.

Signature

(getenv-internal VARIABLE &optional ENV)

Documentation

Get the value of environment variable VARIABLE.

VARIABLE should be a string. Value is nil if VARIABLE is undefined in the environment. Otherwise, value is a string.

This function searches process-environment for VARIABLE.

If optional parameter ENV is a list, then search this list instead of process-environment, and return t when encountering a negative entry
(an entry for a variable with no value).

Source Code

// Defined in /usr/src/emacs/src/callproc.c
{
  char *value;
  ptrdiff_t valuelen;

  CHECK_STRING (variable);
  if (CONSP (env))
    {
      if (getenv_internal_1 (SSDATA (variable), SBYTES (variable),
			     &value, &valuelen, env))
	return value ? make_string (value, valuelen) : Qt;
      else
	return Qnil;
    }
  else if (getenv_internal (SSDATA (variable), SBYTES (variable),
			    &value, &valuelen, env))
    return make_string (value, valuelen);
  else
    return Qnil;
}