Obfuscated brainfuck runtime in 502 bytes of C

bf.c

#include <stdio.h>
#include <stdint.h>
FILE *F;int C,S,D,P,L=30000;uint8_t d[30000];void main(int c,char** v){if(c==2){F=fopen(v[1],"r");while((C=fgetc(F))!=-1){if(C==62)P=(P+1)%L;if(C==60)P=(P+L-1)%L;if(C==43)d[P]++;if(C==45)d[P]--;if(C==46)putchar(d[P]);if(C==44)d[P]=getchar();if(C==91&&d[P]==0){D=1;while(D>0&&(S=fgetc(F))!=-1){if(S==91)D++;if(S==93)D--;}}if(C==93&&d[P]!=0){D=1;fseek(F,-2,1);while(D>0&&ftell(F)>0){fseek(F,-1,1);S=fgetc(F);fseek(F,-1,1);if(S==93)D++;if(S==91)D--;}}};fclose(F);}}

BrainfuCk.md

BrainfuCk

A BF runtime written in C, aiming to put file size over speed.

Any suggestions to improve the obfuscations in the comments are very, very welcome, as I'm new to this type of stuff and would love to learn!

deobfuscated.c

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

#define BUF_LEN 30000
uint8_t datap = 0;
uint8_t data[BUF_LEN];
FILE *filePtr;
int curChar, parScan;

int main(int argc, char** argv) {
    if(argc != 2) {
        return 1;
    }
    filePtr = fopen(argv[1], "r");

    memset(data, 0, BUF_LEN);
    while((curChar = fgetc(filePtr)) != EOF) {
        switch(curChar) {
            case '>':
                datap++;
                break;
            case '<':
                datap--;
                break;
            case '+':
                data[datap]++;
                break;
            case '-':
                data[datap]--;
                break;
            case '.':
                printf("%c", data[datap]);
                break;
            case ',':
                scanf("%c", &data[datap]);
                break;
            case '[':
                if (data[datap] == 0) {
                    int depth = 1;
                    while (depth > 0 && (parScan = fgetc(filePtr)) != EOF) {
                        if (parScan == '[') depth++;
                        else if (parScan == ']') depth--;
                    }
                }
                break;

            case ']':
                if (data[datap] != 0) {
                    int depth = 1;
                    fseek(filePtr, -2, SEEK_CUR);
                    while (depth > 0 && ftell(filePtr) > 0) {
                        fseek(filePtr, -1, SEEK_CUR);
                        parScan = fgetc(filePtr);
                        fseek(filePtr, -1, SEEK_CUR);
                        if (parScan == ']') depth++;
                        else if (parScan == '[') depth--;
                    }
                }
                break;
        }
        if(datap >= BUF_LEN) {
            datap = 0;
        }
    }
    fclose(filePtr);

    return 0;
}