summaryrefslogtreecommitdiff
path: root/manual/examples/argp-ex4.c
diff options
context:
space:
mode:
Diffstat (limited to 'manual/examples/argp-ex4.c')
-rw-r--r--manual/examples/argp-ex4.c144
1 files changed, 144 insertions, 0 deletions
diff --git a/manual/examples/argp-ex4.c b/manual/examples/argp-ex4.c
new file mode 100644
index 0000000000..24dd417a81
--- /dev/null
+++ b/manual/examples/argp-ex4.c
@@ -0,0 +1,144 @@
+/* Argp example #4 -- a program with somewhat more complicated options */
+
+#include <stdlib.h>
+#include <error.h>
+#include <argp.h>
+
+const char *argp_program_version =
+ "argp-ex4 1.0";
+const char *argp_program_bug_address =
+ "<bug-gnu-utils@@prep.ai.mit.edu>";
+
+/* Program documentation. */
+static char doc[] =
+ "Argp example #4 -- a program with somewhat more complicated\
+options\
+\vThis part of the documentation comes *after* the options;\
+ note that the text is automatically filled, but it's possible\
+ to force a line-break, e.g.\n<-- here.";
+
+/* A description of the arguments we accept. */
+static char args_doc[] = "ARG1 [STRING...]";
+
+/* Keys for options without short-options. */
+#define OPT_ABORT 1 /* --abort */
+
+/* The options we understand. */
+static struct argp_option options[] = {
+ {"verbose", 'v', 0, 0, "Produce verbose output" },
+ {"quiet", 'q', 0, 0, "Don't produce any output" },
+ {"silent", 's', 0, OPTION_ALIAS },
+ {"output", 'o', "FILE", 0,
+ "Output to FILE instead of standard output" },
+
+ {0,0,0,0, "The following options should be grouped together:" },
+ {"repeat", 'r', "COUNT", OPTION_ARG_OPTIONAL,
+ "Repeat the output COUNT (default 10) times"},
+ {"abort", OPT_ABORT, 0, 0, "Abort before showing any output"},
+
+ { 0 }
+};
+
+/* Used by @code{main} to communicate with @code{parse_opt}. */
+struct arguments
+{
+ char *arg1; /* @var{arg1} */
+ char **strings; /* [@var{string}@dots{}] */
+ int silent, verbose, abort; /* @samp{-s}, @samp{-v}, @samp{--abort} */
+ char *output_file; /* @var{file} arg to @samp{--output} */
+ int repeat_count; /* @var{count} arg to @samp{--repeat} */
+};
+
+/* Parse a single option. */
+static error_t
+parse_opt (int key, char *arg, struct argp_state *state)
+{
+ /* Get the @code{input} argument from @code{argp_parse}, which we
+ know is a pointer to our arguments structure. */
+ struct arguments *arguments = state->input;
+
+ switch (key)
+ {
+ case 'q': case 's':
+ arguments->silent = 1;
+ break;
+ case 'v':
+ arguments->verbose = 1;
+ break;
+ case 'o':
+ arguments->output_file = arg;
+ break;
+ case 'r':
+ arguments->repeat_count = arg ? atoi (arg) : 10;
+ break;
+ case OPT_ABORT:
+ arguments->abort = 1;
+ break;
+
+ case ARGP_KEY_NO_ARGS:
+ argp_usage (state);
+
+ case ARGP_KEY_ARG:
+ /* Here we know that @code{state->arg_num == 0}, since we
+ force argument parsing to end before any more arguments can
+ get here. */
+ arguments->arg1 = arg;
+
+ /* Now we consume all the rest of the arguments.
+ @code{state->next} is the index in @code{state->argv} of the
+ next argument to be parsed, which is the first @var{string}
+ we're interested in, so we can just use
+ @code{&state->argv[state->next]} as the value for
+ arguments->strings.
+
+ @emph{In addition}, by setting @code{state->next} to the end
+ of the arguments, we can force argp to stop parsing here and
+ return. */
+ arguments->strings = &state->argv[state->next];
+ state->next = state->argc;
+
+ break;
+
+ default:
+ return ARGP_ERR_UNKNOWN;
+ }
+ return 0;
+}
+
+/* Our argp parser. */
+static struct argp argp = { options, parse_opt, args_doc, doc };
+
+int main (int argc, char **argv)
+{
+ int i, j;
+ struct arguments arguments;
+
+ /* Default values. */
+ arguments.silent = 0;
+ arguments.verbose = 0;
+ arguments.output_file = "-";
+ arguments.repeat_count = 1;
+ arguments.abort = 0;
+
+ /* Parse our arguments; every option seen by @code{parse_opt} will be
+ reflected in @code{arguments}. */
+ argp_parse (&argp, argc, argv, 0, 0, &arguments);
+
+ if (arguments.abort)
+ error (10, 0, "ABORTED");
+
+ for (i = 0; i < arguments.repeat_count; i++)
+ {
+ printf ("ARG1 = %s\n", arguments.arg1);
+ printf ("STRINGS = ");
+ for (j = 0; arguments.strings[j]; j++)
+ printf (j == 0 ? "%s" : ", %s", arguments.strings[j]);
+ printf ("\n");
+ printf ("OUTPUT_FILE = %s\nVERBOSE = %s\nSILENT = %s\n",
+ arguments.output_file,
+ arguments.verbose ? "yes" : "no",
+ arguments.silent ? "yes" : "no");
+ }
+
+ exit (0);
+}