space after optional optarg?

[static peak]

If you use getopt() to recieve arguments you can use flags (-e, -d etc). With a semicolon ( -e: ) the flag requires another argument, like this ./nice -e foo

With a double semicolon ( -e:: ) you can have an optional flag argument, but you have to write like this ./nice -efoo

Why did the space disappear and can I get it back?

[celest furnace]

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[rain gyro]

What? I know for a fact that I wrote a program using getopt_long_only where I had the flags

"h::e:d:"
```and I could put a space there just fine

Let me scrape together the most important pieces of the code-puzzle so you can see how I did it (a few years ago 🐒 )

#include <string.h>
#include <stdio.h>
#include <getopt.h>
#include <ctype.h>

#define EQUALS(name, l, s, cl, cs) (!strcmp(name, l) || !strcmp(name, s) || !strcmp(name, cl) || !strcmp(name, cs))
#define SELECT_PARAM optarg ? optarg : (optind < argc ? argv[optind] : "")

int convertOptionNameToChar(char *name) {
    for (char *p = name; *p; ++p) *p = tolower(*p);

    if EQUALS(name, "help", "h", "-help", "-h")
        return 'h';
    else if EQUALS(name, "encode", "e", "-encode", "-e")
        return 'e';
    else if EQUALS(name, "decode", "d", "-decode", "-d")
        return 'd';
    else
        return '?';
}

int main(int argc, char *argv[]) {

    static const struct option long_options[] =
            {
                    {"help", no_argument, 0, 'h'},
                    {"encode", no_argument, 0, 'e'},
                    {"decode", no_argument, 0, 'd'},
                    0
            };


    int index = -1;
    char *filename;

    int result = getopt_long_only(argc, argv, "h::e:d:", long_options, &index);

    if (result != -1) {

        int param = 0;

        switch (result) {
            default:
            case '0':
            case '?':
                param = convertOptionNameToChar("");
                /* FALLTHRU */
            case 'h':
                if (!param)
                    param = convertOptionNameToChar(SELECT_PARAM);

                help(param, argv[0]);
                return 0;
            case 'e':
                filename = SELECT_PARAM;

                encode(filename);
                return 0;
            case 'd':
                filename = SELECT_PARAM;

                decode(filename);
                return 0;
        }
    }

    ...
}

[static peak]

Haha I shouldn't have skimmed through the manual, didn't see that one

Yeah getopt_long works

kinda weird getopt reads optional args differently tho

!solved