Brainf**k transpiler in C

bf.c

#include <stdio.h>
#include <stddef.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

void usage(const char *program_name) {
    printf("Usage: %s <input-file>\n", program_name);
}

void bf_header(FILE *out) {
    fprintf(out, "#include <stdio.h>\n");
    fprintf(out, "unsigned char tape[640000]; // should be enough for everyone\n");
    fprintf(out, "int main() {\n");
    fprintf(out, "    unsigned char *ptr = &tape[0];\n");
}

void bf_footer(FILE *out) {
    fprintf(out, "}\n");
}

void compile_char(FILE *out, char ch) {
    switch (ch) {
        case '+': {
            fprintf(out, "    ++*ptr;\n");
        } break;
        case '-': {
            fprintf(out, "    --*ptr;\n");
        } break;
        case '<': {
            fprintf(out, "    ptr--;\n");
        } break;
        case '>': {
            fprintf(out, "    ptr++;\n");
        } break;
        case '.': {
            fprintf(out, "    putchar(*ptr);\n");
        } break;
        case ',': {
            fprintf(out, "    *ptr = getchar();\n");
        } break;
        case '[': {
            fprintf(out, "    while (*ptr) {\n");
        } break;
        case ']': {
            fprintf(out, "    }\n");
        } break;
    }
}

int main(int argc, char *argv[]) {
    if (argc != 2) {
        usage(argv[0]);
        fprintf(stderr, "ERROR: no input file provided\n");
        return 1;
    }
    argv++;

    FILE *infile = fopen(*argv, "r");
    if (infile == NULL) {
        fprintf(stderr, "ERROR: could not open file %s: %s\n", *argv, strerror(errno));
        return 1;
    }

    const char *out_file_path = "out.c";
    FILE *outfile = fopen(out_file_path, "w");
    if (outfile == NULL) {
        fprintf(stderr, "ERROR: could not open file %s: %s\n", out_file_path, strerror(errno));
        return 1;
    }

    bf_header(outfile);
    char ch;
    while (fread(&ch, 1, 1, infile) != 0) {
        compile_char(outfile, ch);
    }
    puts("");

    fclose(infile);
    bf_footer(outfile);

    fclose(outfile);

    int code = execlp("gcc", "cc", "-o", "out", "out.c", NULL);
    if (code != 0) {
        fprintf(stderr, "ERROR: gcc exited with non-zero code: %d", code);
        return code;
    }

    execlp("rm", "out.c", NULL);
}