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authorUlrich Drepper <drepper@redhat.com>1998-09-01 14:31:49 +0000
committerUlrich Drepper <drepper@redhat.com>1998-09-01 14:31:49 +0000
commit052b6a6c94cc330dfbc09ff7b5f03c943deb7ca2 (patch)
tree0ef4d2730e6e20141e3b669b8a3614193200f3fc /manual/examples
parent85c165befc61d049abe3cc443c275a210c569338 (diff)
Update.
1998-08-09 Geoff Keating <geoffk@ozemail.com.au> * sysdeps/powerpc/Makefile [subdir=elf]: Add new files split out of dl-machine.h. * sysdeps/powerpc/dl-machine.c: New file. * sysdeps/powerpc/dl-machine.h: Move much stuff into separate files. Revise ELF_PREFERRED_ADDRESS to take account of the new mapping information (fixes bug involving huge bloated web browser). Set ELF_MACHINE_PLTREL_OVERLAP. * sysdeps/powerpc/dl-start.S: New file. * elf/dl-load.c (_dl_map_object_from_fd): Initialise l_map_start, l_map_end. * elf/do-rel.h: Call elf_machine_rel only once (to save space). * elf/dynamic-link.h: Allow PLT relocs to be in the middle of the others. Call elf_dynamic_do_##reloc only once (to save even more space). * elf/link.h: Add new members l_map_start and l_map_end to keep track of the memory map. * elf/rtld.c (_dl_start): Initialise l_map_start for ld.so and the executable. 1998-09-01 11:53 Ulrich Drepper <drepper@cygnus.com> * debug/Makefile (catchsegv): We need not rewrite SOVER anymore. Reported by Andreas Jaeger. * posix/glob.h: Use __size_t instead of size_t in definitions and make sure this is defined. * manual/locale.texi: Almost complete rewrite. Document more functions
Diffstat (limited to 'manual/examples')
-rw-r--r--manual/examples/argp-ex1.c5
-rw-r--r--manual/examples/argp-ex2.c21
-rw-r--r--manual/examples/argp-ex3.c54
-rw-r--r--manual/examples/argp-ex4.c23
4 files changed, 101 insertions, 2 deletions
diff --git a/manual/examples/argp-ex1.c b/manual/examples/argp-ex1.c
index c87ebbb532..50ac0ed978 100644
--- a/manual/examples/argp-ex1.c
+++ b/manual/examples/argp-ex1.c
@@ -1,5 +1,10 @@
/* Argp example #1 -- a minimal program using argp */
+/* This is (probably) the smallest possible program that
+ uses argp. It won't do much except give an error
+ messages and exit when there are any arguments, and print
+ a (rather pointless) messages for --help. */
+
#include <argp.h>
int main (int argc, char **argv)
diff --git a/manual/examples/argp-ex2.c b/manual/examples/argp-ex2.c
index d1b149b494..55f59f2ab8 100644
--- a/manual/examples/argp-ex2.c
+++ b/manual/examples/argp-ex2.c
@@ -1,11 +1,30 @@
/* Argp example #2 -- a pretty minimal program using argp */
+/* This program doesn't use any options or arguments, but uses
+ argp to be compliant with the GNU standard command line
+ format.
+
+ In addition to making sure no arguments are given, and
+ implementing a --help option, this example will have a
+ --version option, and will put the given documentation string
+ and bug address in the --help output, as per GNU standards.
+
+ The variable ARGP contains the argument parser specification;
+ adding fields to this structure is the way most parameters are
+ passed to argp_parse (the first three fields are usually used,
+ but not in this small program). There are also two global
+ variables that argp knows about defined here,
+ ARGP_PROGRAM_VERSION and ARGP_PROGRAM_BUG_ADDRESS (they are
+ global variables becuase they will almost always be constant
+ for a given program, even if it uses different argument
+ parsers for various tasks). */
+
#include <argp.h>
const char *argp_program_version =
"argp-ex2 1.0";
const char *argp_program_bug_address =
- "<bug-gnu-utils@@prep.ai.mit.edu>";
+ "<bug-gnu-utils@@gnu.org>";
/* Program documentation. */
static char doc[] =
diff --git a/manual/examples/argp-ex3.c b/manual/examples/argp-ex3.c
index 363ee59e11..87d993f8ae 100644
--- a/manual/examples/argp-ex3.c
+++ b/manual/examples/argp-ex3.c
@@ -1,11 +1,63 @@
/* Argp example #3 -- a program with options and arguments using argp */
+/* This program uses the same features as example 2, and uses options and
+ arguments.
+
+ We now use the first four fields in ARGP, so here's a description of them:
+ OPTIONS -- A pointer to a vector of struct argp_option (see below)
+ PARSER -- A function to parse a single option, called by argp
+ ARGS_DOC -- A string describing how the non-option arguments should look
+ DOC -- A descriptive string about this program; if it contains a
+ vertical tab character (\v), the part after it will be
+ printed *following* the options
+
+ The function PARSER takes the following arguments:
+ KEY -- An integer specifying which option this is (taken
+ from the KEY field in each struct argp_option), or
+ a special key specifying something else; the only
+ special keys we use here are ARGP_KEY_ARG, meaning
+ a non-option argument, and ARGP_KEY_END, meaning
+ that all argumens have been parsed
+ ARG -- For an option KEY, the string value of its
+ argument, or NULL if it has none
+ STATE-- A pointer to a struct argp_state, containing
+ various useful information about the parsing state; used here
+ are the INPUT field, which reflects the INPUT argument to
+ argp_parse, and the ARG_NUM field, which is the number of the
+ current non-option argument being parsed
+ It should return either 0, meaning success, ARGP_ERR_UNKNOWN, meaning the
+ given KEY wasn't recognized, or an errno value indicating some other
+ error.
+
+ Note that in this example, main uses a structure to communicate with the
+ parse_opt function, a pointer to which it passes in the INPUT argument to
+ argp_parse. Of course, it's also possible to use global variables
+ instead, but this is somewhat more flexible.
+
+ The OPTIONS field contains a pointer to a vector of struct argp_option's;
+ that structure has the following fields (if you assign your option
+ structures using array initialization like this example, unspecified
+ fields will be defaulted to 0, and need not be specified):
+ NAME -- The name of this option's long option (may be zero)
+ KEY -- The KEY to pass to the PARSER function when parsing this option,
+ *and* the name of this option's short option, if it is a
+ printable ascii character
+ ARG -- The name of this option's argument, if any
+ FLAGS -- Flags describing this option; some of them are:
+ OPTION_ARG_OPTIONAL -- The argument to this option is optional
+ OPTION_ALIAS -- This option is an alias for the
+ previous option
+ OPTION_HIDDEN -- Don't show this option in --help output
+ DOC -- A documentation string for this option, shown in --help output
+
+ An options vector should be terminated by an option with all fields zero. */
+
#include <argp.h>
const char *argp_program_version =
"argp-ex3 1.0";
const char *argp_program_bug_address =
- "<bug-gnu-utils@@prep.ai.mit.edu>";
+ "<bug-gnu-utils@@gnu.org>";
/* Program documentation. */
static char doc[] =
diff --git a/manual/examples/argp-ex4.c b/manual/examples/argp-ex4.c
index 24dd417a81..fa5a8d00ec 100644
--- a/manual/examples/argp-ex4.c
+++ b/manual/examples/argp-ex4.c
@@ -1,5 +1,28 @@
/* Argp example #4 -- a program with somewhat more complicated options */
+/* This program uses the same features as example 3, but has more
+ options, and somewhat more structure in the -help output. It
+ also shows how you can `steal' the remainder of the input
+ arguments past a certain point, for programs that accept a
+ list of items. It also shows the special argp KEY value
+ ARGP_KEY_NO_ARGS, which is only given if no non-option
+ arguments were supplied to the program.
+
+ For structuring the help output, two features are used,
+ *headers* which are entries in the options vector with the
+ first four fields being zero, and a two part documentation
+ string (in the variable DOC), which allows documentation both
+ before and after the options; the two parts of DOC are
+ separated by a vertical-tab character ('\v', or '\013'). By
+ convention, the documentation before the options is just a
+ short string saying what the program does, and that afterwards
+ is longer, describing the behavior in more detail. All
+ documentation strings are automatically filled for output,
+ although newlines may be included to force a line break at a
+ particular point. All documenation strings are also passed to
+ the `gettext' function, for possible translation into the
+ current locale. */
+
#include <stdlib.h>
#include <error.h>
#include <argp.h>