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Diffstat (limited to 'examples/loadables/tty.c')
-rw-r--r-- | examples/loadables/tty.c | 59 |
1 files changed, 59 insertions, 0 deletions
diff --git a/examples/loadables/tty.c b/examples/loadables/tty.c new file mode 100644 index 0000000..2183123 --- /dev/null +++ b/examples/loadables/tty.c @@ -0,0 +1,59 @@ +/* tty - return terminal name */ + +/* See Makefile for compilation details. */ + +#include "config.h" + +#include <stdio.h> +#include "builtins.h" +#include "shell.h" +#include "bashgetopt.h" + +extern char *ttyname (); + +tty_builtin (list) + WORD_LIST *list; +{ + int opt, sflag; + char *t; + + reset_internal_getopt (); + sflag = 0; + while ((opt = internal_getopt (list, "s")) != -1) + { + switch (opt) + { + case 's': + sflag = 1; + break; + default: + builtin_usage (); + return (EX_USAGE); + } + } + list = loptend; + + t = ttyname (0); + if (sflag == 0) + puts (t ? t : "not a tty"); + return (t ? EXECUTION_SUCCESS : EXECUTION_FAILURE); +} + +char *tty_doc[] = { + "tty writes the name of the terminal that is opened for standard", + "input to standard output. If the `-s' option is supplied, nothing", + "is written; the exit status determines whether or not the standard", + "input is connected to a tty.", + (char *)NULL +}; + +/* The standard structure describing a builtin command. bash keeps an array + of these structures. */ +struct builtin tty_struct = { + "tty", /* builtin name */ + tty_builtin, /* function implementing the builtin */ + BUILTIN_ENABLED, /* initial flags for builtin */ + tty_doc, /* array of long documentation strings. */ + "tty [-s]", /* usage synopsis; becomes short_doc */ + 0 /* reserved for internal use */ +}; |