fscanf() 只拾取文件的第一行 [英] fscanf() only picking up first line of file

问题描述

我有一个制表符分隔文件，我正在尝试将其转换为制表符分隔文件.我正在使用 C.我一直在尝试读取文件的第二行.现在我只有几万行重复第一行.

I have a tab delimited file that I am trying to convert to a tab delimited file. I am using C. I am getting stuck on trying to read the second line of the file. Now I just have an tens of thousand of lines repeating the first line.

#include <stdio.h>
#include <string.h>
#define SELLERCODE  A2LQ9QFN82X636

int main ()
{
     typedef char* string;
     FILE* stream;
     FILE* output;
     string asin[200];
     string sku[15];
     string fnsku[15];
     int quality = 0;

     stream = fopen("c:\\out\\a.txt", "r");
     output = fopen("c:\\out\\output.txt", "w");

     if (stream == NULL)
     { 
         perror("open");
         return 0;
      }

     for(;;)
     {
       fscanf(stream, "%[^\t]\t%[^\t]", sku, fnsku);
       printf("%s\t%s\n",  sku, fnsku);
       fprintf(output, "%s\t%s\t%\t%s\t%s\t%i\n", sku, fnsku, asin, quality);
     }

}

推荐答案

首选 fgets() 读取输入并解析程序中的行，例如使用 sscanf() 或 strtok().

Prefer fgets() to read the input and parse the lines in your program, using, for example, sscanf() or strtok().

fscanf 是出了名的难以使用.
您的 fscanf 在第一行之后没有执行任何转换.
它读取字符直到 TAB，然后忽略 TAB，并读取更多字符直到下一个 TAB.在第二次循环中，sku 没有数据:第一个字符是 TAB.

fscanf is notoriously difficult to use.
Your fscanf is not performing any conversions after the first line.
It reads characters up to a TAB, then ignores the TAB, and reads more characters up to the next TAB. On the 2nd time through the loop, there is no data for sku: the 1st character is a TAB.

请检查返回值.它有很大帮助.

chk = fscanf(stream, "%[^\t]\t%[^\t]", sku, fnsku);
/* 2 conversions: sku and fnsku */
if (chk != 2) {
    /* something went wrong */
}

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