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    <p>Unless your file is huge, if you're using read(), it would be easier to read in the entire file, then operate on the memory buffer, rather than in discrete chunks. That is, unless each line is of a fixed length.</p> <p>I'd do something like this:</p> <pre><code>int rc; int fd = open("data", O_RDONLY); // open the file for reading if (fd == -1) { // error } // to be thorough, do a stat() here to find how big to make the buffer struct stat sb; rc = fstat(fd, &amp;sb); if (rc == -1) { // error } char *buffer = calloc(1, sb.st_size); int bytes_read = 0; // read in entire file; each read() can be incomplete, hence why it's in a loop, // and reading from/writing to increasing sections of the memory and file while ((rc = read(fd, (buffer + bytes_read), (sb.st_size - bytes_read))) &gt; 0) { if (rc == -1) { // error } bytes_read += rc; } close(fd); // Now, to read it line-by-line... char line[128]; // 128 is arbitrary int pos = 0; while ((rc = sscanf(buffer + pos, "%127[^\n]\n", line)) &gt; 0) { pos += strlen(line) + 1; // do stuff with line } return 0; </code></pre> <p>Then you can operate on your memory buffer line-by-line by scanning for newlines, or using sscanf(). Also make sure to free() your buffer!</p> <p><strong>Edit:</strong> I've added some example code for using sscanf() to handle your buffer. If you know the format of the lines (you say you're parsing them) you might be able to make better use of sscanf() by using the format specifiers. All of this is untested, by the way.</p>
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    1. COI dont want to read the entire file in the first read. I want to read it line by line... or perhaps a big buffer for the entire file and then scan it line by line into a lower buffer. how can I do this?
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    2. COEdited with an example.
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    3. COI get a segmentation fault at sscanf() can u pls check?
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