linux 内核 遍历进程

#include <stdio.h>
#include <dirent.h>
#include <string.h>
#include <sys/types.h>

int main() {
    DIR *dir;
    struct dirent *entry;
    char path[] = "/proc/";
    char buffer[256];

    dir = opendir("/proc");
    if (dir == NULL) {
        perror("opendir(/proc)");
        return 1;
    }

    while ((entry = readdir(dir)) != NULL) {
        if (entry->d_type == DT_DIR && entry->d_name[0] >= '0' && entry->d_name[0] <= '9') {
            snprintf(buffer, sizeof(buffer), "%s%s/cmdline", path, entry->d_name);
            FILE *fp = fopen(buffer, "r");
            if (fp) {
                fgets(buffer, sizeof(buffer), fp);
                printf("PID: %s, CMD: %s\n", entry->d_name, buffer);
                fclose(fp);
            }
        }
    }

    closedir(dir);
    return 0;
}