c - fputc/fprintf 无法写入我的文件

Question

我应该编写一个程序来获取文本文件(包含纯文本)并更正以下错误(涉及标点符号):

Hello , there! --> Hello, there!
Hello ,there! --> Hello, there!
A sentence. this should be capitalized --> A sentence. This should be capitalized

我提出的算法如下:我逐行遍历文本文件，并将每一行传递给错误查找器函数。此函数检测上述(第一个和第二个)错误并在错误数组中存储一个 double 。整数部分表示错误开始的位置，小数部分表示发现错误的类型。

例如，如果我将 "Hello , there!" 作为参数传递，则存储在数组中的 double 为 5.1，因为错误从字符串的第 5 个字符开始，而 0.1 是因为这是第一种错误。

类似地，"Hello ,there!" 会将 5.2 存储在数组中(第二种类型的错误)。找到错误后，一段代码将新的更正行写入不同的文件。

FILE *src, *dst; //source file, destination file
int ptr; //shows how many mistakes were found in the line 
src = fopen((const char*)filename, "r"); //opening both files
dst = fopen("temp.txt", "w");
char array[1024];
double mistakes[1024];
double mistakeType, position;
int i, j, pos = 0, capitalNeeded = 1; //capitalNeeded shows whether the next letter should be capitalized


while(fgets(array, 1024, src)!=NULL){ //taking the content of the file line by line
    puts(array);
    ptr = findMistakes(array, mistakes); //the mistakes of the current line are located, and their types are defined

    for(i=0; i<ptr; i++){ //looping through the mistakes
        if(capitalNeeded && isalpha(array[pos])){
            array[pos] = toupper(array[pos]);
            capitalNeeded = 0;
        }
        mistakeType = modf(mistakes[i], &position); //position will be of type int.0000..
        for(j=pos; j<position; j++){
            if(array[j] == '.' || array[j] == '?' ||array[j] == '!'){ //testing if a capital letter is needed
                capitalNeeded = 1;
            }
            if(capitalNeeded && isalpha(array[j])){
                array[j] = toupper(array[j]);
                capitalNeeded = 0;
            }
        }
        pos = j+1; //pos becomes the last j+1, basically shows the next character to be read from the array

        if(mistakeType == 0.1){ //if mistake was of type 1
            //then pos points to a space character ' '. The space is bypassed and the next 
            //character is placed in the file
            fprintf(dst, "%c", array[pos+1]); //which is a punctuation character
            fprintf(dst, "%c", array[pos+2]); //then a space is placed
            pos += 3; //the next character to be read and placed becomes pos+3
        }
        else{ //only 2 type of mistakes exist, so if it's not of type 1 then it's of type 2
            //In a type 2 mistake the punctuation mark is attached to the next letter
            //pos currently points to a space character ' ', and pos+1 to a punctuation mark.
            fprintf(dst, "%c", array[pos+1]);
            fprintf(dst, "%c", array[pos]);
            pos += 2; //the next character to be read and placed becomes pos+2
        }
    }
    fprintf(dst, "%c", '\n'); //the line is changed
    pos = 0; //pos is reset, and readied for the processing of the next line


}

但是，我无法判断我的算法是否有效，因为 fputc 将不起作用。编译没有错误，但是新文件是空的。我知道 fputc() 采用 int 参数，所以我尝试使用 fprintf(dst, "%c", array[...]);，但产生了完全相同的结果。我搜索但找不到答案，感谢任何帮助...

Answer 1

Valgrind 出现错误关于你的代码。

   ==20508== Use of uninitialised value of size 8
    ==20508==    at 0x4EA7A9E: fgets (iofgets.c:47)
    ==20508==    by 0x400D0E: main (in /home/dac/ClionProjects/replace/a.out)
    ==20508== 
    ==20508== Invalid read of size 4
    ==20508==    at 0x4EA7A9E: fgets (iofgets.c:47)
    ==20508==    by 0x400D0E: main (in /home/dac/ClionProjects/replace/a.out)
    ==20508==  Address 0x0 is not stack'd, malloc'd or (recently) free'd

我建议你使用字符串替换。我希望这个例子可以帮助你。

temp.txt

Hello , there! Hello ,there! A sentence. this should be capitalized

(我们将把空格作为字符串进行操作，并将其写入文件file.txt)

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

// You must free the result if result is non-NULL.
char *str_replace(char *orig, char *rep, char *with) {
    char *result; // the return string
    char *ins;    // the next insert point
    char *tmp;    // varies
    int len_rep;  // length of rep
    int len_with; // length of with
    int len_front; // distance between rep and end of last rep
    int count;    // number of replacements

    if (!orig)
        return NULL;
    if (!rep)
        rep = "";
    len_rep = strlen(rep);
    if (!with)
        with = "";
    len_with = strlen(with);

    ins = orig;
    for (count = 0; tmp = strstr(ins, rep); ++count) {
        ins = tmp + len_rep;
    }

    // first time through the loop, all the variable are set correctly
    // from here on,
    //    tmp points to the end of the result string
    //    ins points to the next occurrence of rep in orig
    //    orig points to the remainder of orig after "end of rep"
    tmp = result = malloc(strlen(orig) + (len_with - len_rep) * count + 1);

    if (!result)
        return NULL;

    while (count--) {
        ins = strstr(orig, rep);
        len_front = ins - orig;
        tmp = strncpy(tmp, orig, len_front) + len_front;
        tmp = strcpy(tmp, with) + len_with;
        orig += len_front + len_rep; // move to next "end of rep"
    }
    strcpy(tmp, orig);
    return result;
}
char * Cap(char *string) {
    int i;
    int x = strlen(string); // You want to get the length of the whole string.
    for (i=2;i<x;i++){
        if (isalpha(string[i]) && string[i-1] == ' ' && string[i-2] == '.'){
            // only first letters of a word.
            string[i]= toupper(string[i]);
        }
    }
    return string;
}
void adx_store_data(const char *filepath, const char *data)
{
    FILE *fp = fopen(filepath, "ab");
    if (fp != NULL)
    {
        fputs(data, fp);
        fclose(fp);
    }
}
int main(void)
{
    FILE * fp;
    char * line = NULL;
    size_t len = 0;
    ssize_t read;
    // char *s = str_replace("aaabaa", 'b', "ccccc");
    //   printf("%s\n", s);
    //  free(s);
    fp = fopen("/home/dac/ClionProjects/replace/temp.txt", "r");
    if (fp == NULL)
        exit(EXIT_FAILURE);

    while ((read = getline(&line, &len, fp)) != -1) {
        printf("Retrieved line of length %zu :\n", read);
        printf("%s\n", line);
        str_replace(line, "e", ",");
        line = str_replace(line, " ,", ",");
        line = str_replace(line, ",", ", ");
        line =  str_replace(line, "  ", " ");
        printf("Output: %s",  Cap(line));
        line = Cap(line);
    }
    FILE *f = fopen("file.txt", "w");
    if (f == NULL)
    {
        printf("Error opening file!\n");
        exit(1);
    }

/* print some text */
  //  const char *text = "Write this to the file";
    fprintf(f, "%s\n", line);


    fclose(f);
    fclose(fp);
    if (line)
        free(line);
    exit(EXIT_SUCCESS);
}

测试它:

Retrieved line of length 67 :
Hello , there! Hello ,there! A sentence. this should be capitalized
Output: Hello, there! Hello, there! A sentence. This should be capitalized