examples/loadables/printenv.c

   1 /*
   2  * printenv -- minimal builtin clone of BSD printenv(1).
   3  *
   4  * usage: printenv [varname]
   5  *
   6  */
   7
   8 #include <config.h>
   9 #include <stdio.h>
  10
  11 #include "builtins.h"
  12 #include "shell.h"
  13 #include "bashgetopt.h"
  14
  15 extern char **export_env;
  16
  17 int
  18 printenv_builtin (list)
  19      WORD_LIST *list;
  20 {
  21   register char **envp;
  22   int opt;
  23   SHELL_VAR *var;
  24
  25   reset_internal_getopt ();
  26   while ((opt = internal_getopt (list, "")) != -1)
  27     {
  28       switch (opt)
  29         {
  30         default:
  31           builtin_usage ();
  32           return (EX_USAGE);
  33         }
  34     }
  35   list = loptend;
  36
  37   /* printenv */
  38   if (list == 0)
  39     {
  40       maybe_make_export_env ();         /* this allows minimal code */
  41       for (envp = export_env; *envp; envp++)
  42         printf ("%s\n", *envp);
  43       return (EXECUTION_SUCCESS);
  44     }
  45
  46   /* printenv varname */
  47   var = find_variable (list->word->word);
  48   if (var == 0 || (exported_p (var) == 0))
  49     return (EXECUTION_FAILURE);
  50
  51   if (function_p (var))
  52     print_var_function (var);
  53   else
  54     print_var_value (var, 0);
  55
  56   return (EXECUTION_SUCCESS);
  57 }
  58
  59 char *printenv_doc[] = {
  60         "print values of environment variables",
  61         (char *)NULL
  62 };
  63
  64 struct builtin printenv_struct = {
  65         "printenv",
  66         printenv_builtin,
  67         BUILTIN_ENABLED,
  68         printenv_doc,
  69         "printenv [varname]",
  70         0
  71 };