This is a lighweight C command line argument library which does not require any malloc. It is currently compiled and tested under Linux, FreeBSD, macOS and Windows.
Please have a look at the reference for detailed information. Some features this library includes:
- cross-platform on windows, linux and macOS
- simple interface - just one header
- one simple loop - to iterate over the arguments
- automatic help output - showing all options available
- long and short options - giving users alternatives
- option values - for options which are more than just flags
- no malloc needed - for situations where that's not available
Building, embedding and testing instructions are available in the documentation (it's very easy).
All the documentation is available in the the github page of this repository.
First define the options:
static struct cag_option options[] = {
{.identifier = 's',
.access_letters = "s",
.access_name = NULL,
.value_name = NULL,
.description = "Simple flag"},
{.identifier = 'm',
.access_letters = "mMoO",
.access_name = NULL,
.value_name = NULL,
.description = "Multiple access letters"},
{.identifier = 'l',
.access_letters = NULL,
.access_name = "long",
.value_name = NULL,
.description = "Long parameter name"},
{.identifier = 'k',
.access_letters = "k",
.access_name = "key",
.value_name = "VALUE",
.description = "Parameter value"},
{.identifier = 'h',
.access_letters = "h",
.access_name = "help",
.description = "Shows the command help"}};
And then just iterate argv
:
int main(int argc, char *argv[])
{
bool simple_flag = false, multiple_flag = false, long_flag = false;
const char *value = NULL;
int param_index;
cag_option_context context;
cag_option_init(&context, options, CAG_ARRAY_SIZE(options), argc, argv);
while (cag_option_fetch(&context)) {
switch (cag_option_get_identifier(&context)) {
case 's':
simple_flag = true;
break;
case 'm':
multiple_flag = true;
break;
case 'l':
long_flag = true;
break;
case 'k':
value = cag_option_get_value(&context);
break;
case 'h':
printf("Usage: cargsdemo [OPTION]...\n");
printf("Demonstrates the cargs library.\n\n");
cag_option_print(options, CAG_ARRAY_SIZE(options), stdout);
return EXIT_SUCCESS;
case '?':
cag_option_print_error(&context, stdout);
break;
}
}
printf("simple_flag: %i, multiple_flag: %i, long_flag: %i, key: %s\n",
simple_flag, multiple_flag, long_flag, value ? value : "-");
return EXIT_SUCCESS;
}
foo@bar:~$ ./cargsdemo
simple_flag: 0, multiple_flag: 0, long_flag: 0, key: -
foo@bar:~$ ./cargsdemo -k=test -sm --long
simple_flag: 1, multiple_flag: 1, long_flag: 1, key: test
foo@bar:~$ ./cargsdemo --help
Usage: cargsdemo [OPTION]...
Demonstrates the cargs library.
-s Simple flag
-m, -M, -o, -O Multiple access letters
--long Long parameter name
-k, --key=VALUE Parameter value
-h, --help Shows the command help
Note that all formatting is done by cargs.
The complete example can be found in the ./demo/
folder of this repository.