File and IO Extensions

Overview

The I/O extensions library provides high level file and path manipulation functions.

Features

• Simple read, write and append text files.

• File information functions.

• Standard input and output redirect.

• Path manipulation functions.

• List files in a folder.

Reading and Writing Files

The library provides a simple mechanism to read and write text to files.

#include <c-craft/io.h>

MEM_SCOPE mem = sm_create(0);

char *data = "This is some data for a file";
char *extra = ", and this is appended.";

write_file("tmp.txt", data);
append_file("tmp.txt", extra);
char *buf = read_file(mem, "tmp.txt");

sm_free(mem);   /* Clean up when done */

File Information

Check if a file exists, or find the size of an existing file.

#include <c-craft/io.h>

char *file = "myfile.txt";

if(file_exists(file))
{
    long size = get_fsize(file);
    printf("%s size is %ld bytes.\n", file, size);
}

else
    printf("%s not found.\n", file);

Create Full Path

Use mkpath to create a complete folder path.

#include <c-craft/io.h>

char *path = "/tmp/this/is/a/path";
mkpath(path);

Or use mkpath_to to create a complete folder path to a file.

#include <c-craft/io.h>

char *file = "/tmp/this/is/a/path/to/myfile.txt";
mkpath_to(file);

Listing Folders

Folder contents may be listed like this:

#include <c-craft/io.h>

MEM_SCOPE mem = sm_create(0);

LIST_STR *files = list_dir(mem, "folder/", FALSE);

int i = 0;
char *file = list_str_first(files, NULL);
while (file)
{
    printf("%s\n", file);
    file = list_str_next(files, NULL);
}

sm_free(mem);

Note that ‘.’ and ‘..’ are never returned, they are implicit. Also the trailing ‘/’ for folders in this library is critical. Folder listings will show a trailing ‘/’ for sub-directory names, and failing to specify a trailing ‘/’ will result in no files found.