v0.40: Create exercises. Challenge the community.

parse_flags

Your mission

Build a tiny getopt-style flag parser that walks argv left to right and announces each recognised short option as soon as it appears.

See it in action

./parse_flags -l

Expected result

Option l

Your checklist

For your own tracking. Tests grade your code.

The program understands three short flags: -l, -c, and -p. The -p flag is followed by a separate argv entry used as its value.
For every -l encountered, print exactly Option l\n. For every -c, print Option c\n. For every -p value, print Option p with arg value\n where value is the following argv entry verbatim.
Each argv token is inspected on its own; combined short flags such as -lc are not supported. Tokens that look like flags but are not -l, -c, or -p are silently ignored.
Stop scanning as soon as you reach a token that does not begin with -, or as soon as you reach the literal --. Everything after that is treated as a positional argument and produces no output.
If no extra arguments are supplied, the program prints nothing and exits cleanly.
Use only the write system call for output.

More examples

./parse_flags -p shipit -l

Expected result

Option p with arg shipit
Option l

./parse_flags -l deploy.log -c

Expected result

Option l

Constraints

Expected files

parse_flags.c

Allowed functions

write

parse_flags

Parsing and formats

Your mission

Build a tiny getopt-style flag parser that walks argv left to right and announces each recognised short option as soon as it appears.

See it in action

./parse_flags -l

Expected result

Option l

Your checklist

For your own tracking. Tests grade your code.

The program understands three short flags: -l, -c, and -p. The -p flag is followed by a separate argv entry used as its value.
For every -l encountered, print exactly Option l\n. For every -c, print Option c\n. For every -p value, print Option p with arg value\n where value is the following argv entry verbatim.
Each argv token is inspected on its own; combined short flags such as -lc are not supported. Tokens that look like flags but are not -l, -c, or -p are silently ignored.
Stop scanning as soon as you reach a token that does not begin with -, or as soon as you reach the literal --. Everything after that is treated as a positional argument and produces no output.
If no extra arguments are supplied, the program prints nothing and exits cleanly.
Use only the write system call for output.

More examples

./parse_flags -p shipit -l

Expected result

Option p with arg shipit
Option l

./parse_flags -l deploy.log -c

Expected result

Option l

Constraints

Expected files

parse_flags.c

Allowed functions

write

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01No arguments produces no outputWaiting

02Single -l flagWaiting

03Single -c flagWaiting

04-p flag captures the following argumentWaiting

05All three flags reported in encounter orderWaiting

06Unknown short flags are skipped silentlyWaiting

07Non-flag token stops further parsingWaiting

08-p value then -l preserves orderWaiting

09-- terminates flag parsingWaiting

parse_flags

Your mission

Build a tiny getopt-style flag parser that walks argv left to right and announces each recognised short option as soon as it appears.

See it in action

./parse_flags -l

Expected result

Option l

Your checklist

For your own tracking. Tests grade your code.

The program understands three short flags: -l, -c, and -p. The -p flag is followed by a separate argv entry used as its value.
For every -l encountered, print exactly Option l\n. For every -c, print Option c\n. For every -p value, print Option p with arg value\n where value is the following argv entry verbatim.
Each argv token is inspected on its own; combined short flags such as -lc are not supported. Tokens that look like flags but are not -l, -c, or -p are silently ignored.
Stop scanning as soon as you reach a token that does not begin with -, or as soon as you reach the literal --. Everything after that is treated as a positional argument and produces no output.
If no extra arguments are supplied, the program prints nothing and exits cleanly.
Use only the write system call for output.

More examples

./parse_flags -p shipit -l

Expected result

Option p with arg shipit
Option l

./parse_flags -l deploy.log -c

Expected result

Option l

Constraints

Expected files

parse_flags.c

Allowed functions

write

parse_flags

Parsing and formats

Your mission

Build a tiny getopt-style flag parser that walks argv left to right and announces each recognised short option as soon as it appears.

See it in action

./parse_flags -l

Expected result

Option l

Your checklist

For your own tracking. Tests grade your code.

The program understands three short flags: -l, -c, and -p. The -p flag is followed by a separate argv entry used as its value.
For every -l encountered, print exactly Option l\n. For every -c, print Option c\n. For every -p value, print Option p with arg value\n where value is the following argv entry verbatim.
Each argv token is inspected on its own; combined short flags such as -lc are not supported. Tokens that look like flags but are not -l, -c, or -p are silently ignored.
Stop scanning as soon as you reach a token that does not begin with -, or as soon as you reach the literal --. Everything after that is treated as a positional argument and produces no output.
If no extra arguments are supplied, the program prints nothing and exits cleanly.
Use only the write system call for output.

More examples

./parse_flags -p shipit -l

Expected result

Option p with arg shipit
Option l

./parse_flags -l deploy.log -c

Expected result

Option l

Constraints

Expected files

parse_flags.c

Allowed functions

write

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01No arguments produces no outputWaiting

02Single -l flagWaiting

03Single -c flagWaiting

04-p flag captures the following argumentWaiting

05All three flags reported in encounter orderWaiting

06Unknown short flags are skipped silentlyWaiting

07Non-flag token stops further parsingWaiting

08-p value then -l preserves orderWaiting

09-- terminates flag parsingWaiting

v0.40: Create exercises. Challenge the community.

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