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Comments on How can I modify the code above to accept string as user input and use strcmp to compare with the contents of the text file & then delete that line?

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How can I modify the code above to accept string as user input and use strcmp to compare with the contents of the text file & then delete that line?

+1
−4

I want to enter a string to compare with the text file, and if that word matches, then I want to delete that line containing that string. How can I modify the code below, since the code below takes line number as input to delete a specific line. Thank you.

#include <stdio.h>
    
int main()
{
    FILE *fileptr1, *fileptr2;
    char filename[40];
    char ch;
    int delete_line, temp = 1;
    printf("Enter file name: ");
    scanf("%s", filename);
    //open file in read mode
    fileptr1 = fopen(filename, "r");
    ch = getc(fileptr1);
    while (ch != EOF)
    {
        printf("%c", ch);
        ch = getc(fileptr1);
    }
    //rewind
    rewind(fileptr1);
    printf(" \n Enter line number of the line to be deleted:");
    scanf("%d", &delete_line);
    //open new file in write mode
    fileptr2 = fopen("replica.c", "w");
    ch = 'A';
    while (ch != EOF)
    {
        ch = getc(fileptr1);
        //except the line to be deleted
        if (temp != delete_line)
        {
            //copy all lines in file replica.c
            putc(ch, fileptr2);
        }
        if (ch == '\n')
        {
            temp++;
        }
    }
    fclose(fileptr1);
    fclose(fileptr2);
    remove(filename);
    //rename the file replica.c to original name
    rename("replica.c", filename);
    printf("\n The contents of file after being modified are as follows:\n");
    fileptr1 = fopen(filename, "r");
    ch = getc(fileptr1);
    while (ch != EOF)
    {
        printf("%c", ch);
        ch = getc(fileptr1);
    }
    fclose(fileptr1);
    return 0;
}

Example of contents in text file: hello world up one two three User input: hello Updated contents in text file: one two three

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3 comment threads

ch needs to be int (1 comment)
Does it really need to be words (in the lexical sense)? (1 comment)
Why is your question quoted? (3 comments)
ch needs to be int
Lundin‭ wrote about 3 years ago

Any variable dealing with EOF must be int, not char.