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Toby Speight
Toby Speight
  • 88.7k
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  • 104
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Simple cmdcommand line parsing

I'm making a project that needs a simple cross-platform cmd linecommand-line parser,. I made this. Hope you enjoy!

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    whoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                  {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    whoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                  {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}

Simple cmd line parsing

I'm making a project that needs a simple cross-platform cmd line parser, I made this. Hope you enjoy!

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    whoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                  {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}

Simple command line parsing

I'm making a project that needs a simple cross-platform command-line parser. I made this. Hope you enjoy!

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    whoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                  {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}
Bumped by Community user
Added whoami to the help message
Source Link
Alex Angel
Alex Angel
  • 527
  • 5
  • 14
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    progNamewhoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                            {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    progName);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                            {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    char * whoami = 0;
    (whoami = strrchr(progName, '/')) ? ++whoami : (whoami = progName);
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    whoami);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                  {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}
added 2 characters in body
Source Link
Reinderien
Reinderien
  • 71.2k
  • 5
  • 76
  • 257
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    progName);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                            {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}
 
```

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    progName);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                            {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}
 
```

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>

#define __NUM_OF_ELEMENTS(ARR) (sizeof(ARR)/sizeof(ARR[0]))
#define __HAS_ARG(FLAGS, ARG) (FLAGS & (1 << ARG))


void panic(const char *fmt, ...){
    fprintf(stderr, "error: ");

    va_list arglist;
    va_start( arglist, fmt );
    vfprintf(stderr, fmt, arglist);
    va_end( arglist );

    exit(EXIT_FAILURE);
}

void help(const char * progName){
    printf(

           "%s is intended to do blah\n"
           "Options:\n"
           " --help                Display This message\n"
           " --file [file name]    Input file to use\n",

    progName);
    exit(EXIT_SUCCESS);
}

int main(int argc, char *argv[])
{
    if(argc == 1){
        help(argv[0]);
    }

    const char * args[] = {"--help", "--file", "--2cool4scool"};
    enum                            {HELP_ARG, FILE_ARG, TOO_COOL_FOR_SCHOOL_ARG};
    unsigned int flags = 0;

    //skip prog name
    for(unsigned int arg = 1, i = 0; arg < argc; ++arg){
        for(i = 0; i < (unsigned int)__NUM_OF_ELEMENTS(args); ++i){
            if(!strcmp(argv[arg], args[i])){
                flags |= 1 << i;
                goto CMD_ARGUMENT_FOUND;
            }
        }


        //argument is not found / unkown arg
        panic("Argument '%s' not found\n", argv[arg]);


        CMD_ARGUMENT_FOUND:;
    }

    if(__HAS_ARG(flags, HELP_ARG)){
        help(argv[0]);
    }
    if(__HAS_ARG(flags, TOO_COOL_FOR_SCHOOL_ARG)){
        puts("Hell YA!");
    }

    return 0;
}
removed "constexpr" from args[] as that is a C++ operator
Source Link
Alex Angel
Alex Angel
  • 527
  • 5
  • 14
Source Link
Alex Angel
Alex Angel
  • 527
  • 5
  • 14