c – 如何稳健地写入缓慢且不可靠的NFS

我不是C的专家,我正在寻找一些建议,以使我的程序更健壮和可靠.只是为了给出一些背景信息：我编写了一个程序来做一些科学计算,需要花费很长时间(大约20小时)才能在大型HPC linux集群上使用SLRUM调度系统和NFS挂载文件系统执行.似乎发生的事情是,在20小时的某个时间,与文件系统的连接变得陈旧(在整个机器上;独立于我的程序)和第一次打开&写一个文件需要很长时间,这会导致我迄今为止无法精确跟踪的段错误转储错误.下面是一个至少在概念上重现错误的最小文件：程序启动,打开文件,一切正常.该程序进行了一些长时间的计算(由sleep()模拟),试图打开&再次写入同一文件,它失败了.什么是一些约定,使我的代码更健壮,可靠地将我的结果写入文件而不会崩溃？

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc,char **argv) {
    // Declare variables
    FILE *outfile;
    char outname[150] = "result.csv";

    // Open file for writing
    printf("CHECKING if output file '%s' is writable?",outname);
    outfile=fopen(outname,"w");
    if (outfile == NULL) {
        perror("Failed: ");
        exit(EXIT_FAILURE);
    }
    fclose(outfile);
    printf(" PASSED.n");

    // Do some computation that takes really long (around 19h)
    sleep(3);

    // Open file again and Write results
    printf("Writing results to %s ...","w");
    if (outfile == NULL) {
        perror("Failed writing in tabulate_vector_new: ");
        exit(EXIT_FAILURE);
    }
    fprintf( outfile,"This is the important result.n");
    fclose(outfile);

    printf(" DONE.n");
    return 0;
}

pid_t pid = fork();

if (pid == -1)
{
    // error,failed to fork(). should probably give up now. something is really wrong.
} 
else if (pid > 0)
{
    // if the child exits,it has successfully interacted with the NFS file system
    wait(NULL);
    // proceed with attempting to write important data
}
else 
{
    // we are the child; fork df in order to test the NFS file system
    execlp("df","df","/mnt",(char *)NULL)
    // the child has been replaced by df,which will try to statfs(2) /mnt for us
}