Exchange contents from one text file to other

The code is working nice for me.


But feel free to give me advice.

Code:

---

#include <stdio.h>
#include <stdlib.h>
#define SIZE 100


int main(int argc, char** argv) {


    // Transfer the contents from on file to the other.
    FILE *pFileA;
    FILE *pFileB;
    FILE *pFileTemp;


    char buffer[SIZE];


    // Copy codeA to a temp file
    if ((pFileA = fopen("codeA.txt", "rt")) == NULL)
        return -1;


    if ((pFileTemp = fopen("temp.txt", "wt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileA) != NULL)
        fprintf(pFileTemp, "%s", buffer);


    fclose(pFileA);
    fclose(pFileTemp);


    // Copy codeB to codeA
    if ((pFileA = fopen("codeA.txt", "wt")) == NULL)
        return -1;


    if ((pFileB = fopen("codeB.txt", "rt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileB) != NULL)
        fprintf(pFileA, "%s", buffer);


    fclose(pFileA);
    fclose(pFileB);


    // Copy tempFile to codeB
    if ((pFileTemp = fopen("temp.txt", "rt")) == NULL)
        return -1;


    if ((pFileB = fopen("codeB.txt", "wt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileTemp) != NULL)
        fprintf(pFileB, "%s", buffer);


    fclose(pFileTemp);
    fclose(pFileB);


    // Remove temp
    remove("temp.txt");


    return (EXIT_SUCCESS);
}

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How many of these homework assignments are you going to post?

First of all, you didn't listen to @Salem's advice in an earlier post. If you will not take our advice, then why should we continue to respond to your posts?

As for this post:

Why are you creating a temp file at all?

Rename codeA.txt to temp.txt

rename codeB.txt to codeA.txt

rename temp.txt to codeB.txt

This could easily be done in a bash script, or a Windows batch file. No need to code this in C, unless your instructor has given you a specific assignment.

Quote:

---

Originally Posted by rstanley

How many of these homework assignments are you going to post?

First of all, you didn't listen to @Salem's advice in an earlier post. If you will not take our advice, then why should we continue to respond to your posts?

As for this post:

Why are you creating a temp file at all?

Rename codeA.txt to temp.txt

rename codeB.txt to codeA.txt

rename temp.txt to codeB.txt

This could easily be done in a bash script, or a Windows batch file. No need to code this in C, unless your instructor has given you a specific assignment.

---

I am study for a exam and i failed on little things so i am posting a lot of that ones.

I think that if you want to "build a house" you should get good bricks and sometimes even the things are working i don´t know if the bricks are in "good shape".

I skip the argv because it was faster to code, but i understand it.

But yeah i can put the arguments inside de IDE, going to start to do that.

This need to be specific in C.

Code:

---



#include <stdio.h>
#include <stdlib.h>
#define SIZE 100


int main(int argc, char** argv) {


    // Transfer the contents from on file to the other.
    FILE *pFileA; // argv[1]
    FILE *pFileB; // argv[2]
    FILE *pFileTemp;


    char buffer[SIZE];


    if (argc != 3) {
        printf("\n- Invalid Sintax: %s Origin(file) Destination(file)\n- Ex: %s CodeA.txt CodeB.Txt\n\n", argv[0], argv[0]);
        return -1;
    }


    // Copy codeA to a temp file
    if ((pFileA = fopen(argv[1], "rt")) == NULL)
        return -1;


    if ((pFileTemp = fopen("temp.txt", "wt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileA) != NULL)
        fprintf(pFileTemp, "%s", buffer);


    fclose(pFileA);
    fclose(pFileTemp);


    // Copy codeB to codeA
    if ((pFileA = fopen(argv[1], "wt")) == NULL)
        return -1;


    if ((pFileB = fopen(argv[2], "rt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileB) != NULL)
        fprintf(pFileA, "%s", buffer);


    fclose(pFileA);
    fclose(pFileB);


    // Copy tempFile to codeB
    if ((pFileTemp = fopen("temp.txt", "rt")) == NULL)
        return -1;


    if ((pFileB = fopen(argv[2], "wt")) == NULL)
        return -1;


    while (fgets(buffer, sizeof (buffer), pFileTemp) != NULL)
        fprintf(pFileB, "%s", buffer);


    fclose(pFileTemp);
    fclose(pFileB);


    // Remove temp
    remove("temp.txt");


    return (EXIT_SUCCESS);
}

---

> This need to be specific in C.
rename(2): change name/location of file - Linux man page is part of standard C.

Quote:

---

Originally Posted by Salem

> This need to be specific in C.
rename(2): change name/location of file - Linux man page is part of standard C.

---

Code:

---


    if (argc != 3) {
        printf("\n- Invalid Sintax: %s Origin(file) Destination(file)\n- Ex: %s CodeA.txt CodeB.Txt\n\n", argv[0], argv[0]);
        return -1;
    }


    rename(argv[1], "temp.txt");
    rename(argv[2], argv[1]);
    rename("temp.txt", argv[2]);
    remove("temp.txt");

---

Quote:

---

Originally Posted by thinkabout

Code:

---


    if (argc != 3) {
        printf("\n- Invalid Sintax: %s Origin(file) Destination(file)\n- Ex: %s CodeA.txt CodeB.Txt\n\n", argv[0], argv[0]);
        return -1;
    }


    rename(argv[1], "temp.txt");
    rename(argv[2], argv[1]);
    rename("temp.txt", argv[2]);
    remove("temp.txt");

---

---

Why do you not error check the renames to insure everything worked?

Code:

---

    rename("temp.txt", argv[2]);
    remove("temp.txt");

---

You renamed "temp.txt", so no need to remove a fie that no longer exists!

Quote:

---

Originally Posted by rstanley

Why do you not error check the renames to insure everything worked?

Code:

---

    rename("temp.txt", argv[2]);
    remove("temp.txt");

---

You renamed "temp.txt", so no need to remove a fie that no longer exists!

---

Code:

---

    // rename - 0 on sucess , -1 on error.
    if (rename(argv[1], "temp.txt") == -1)
        return -1;


    if (rename(argv[2], argv[1]) == -1)
        return -1;


    if (rename("temp.txt", argv[2]) == -1)
        return -1;

---