Test Perror

Task

Implement test_fopen and test_chdir

• test_fopen
  • Try to open a file
  • If it fails, call perror("open") and return -1
  • If success, close it and return 0
• test_chdir
  • Try to change directory
  • If it fails, call perror("cd") and return -1
  • If success, return 0

Function Signature

// Try to open filepath. If fopen fails, call perror("open") and return -1.
// If success, close file and return 0.
int test_fopen(const char* filepath);
 
// Try to chdir to path. If chdir fails, call perror("cd") and return -1.
// If success, return 0.
int test_chdir(const char* path);

What is perror()

void perror(const char* s)

• Produces a message on stderr describing the last error encountered during a library function / system call
• When printing the error message, perror() prints in this format:

<s>: <error message>

• Consider an example where we try to open a nonexistent file using fopen(), the call should fail and not return a valid FILE pointer, in which case, we call perror() to report the problem perror("open") prints open: No such file or directory

NOTE

Use man or other resources to see what fopen and chdir will return upon error

---

Example

$ gcc test_perror.c -o test_perror
$ ./test_perror
open /nonexistent.txt
open: No such file or directory
open test_perror.c
success
cd /nonexistent_dir
cd: No such file or directory
cd .
success

---

Code

int test_fopen(const char *filepath)
{
    FILE *file;
    file = fopen(filepath, "r");
 
    if(file == NULL){
        perror("open");
        return -1;
    }
 
    fclose(file);
    return 0;
}
 
int test_chdir(const char *path)
{
    if(chdir(path) == 0){ return 0;}
    else{
        perror("cd");
        return -1;
    }
}