We had earlier written a program that counts the total number of characters present in a file. If we use that program to count the number of characters present in the above poem (stored in the file “POEM.TXT”), it would give us the character count as 101. The same file if seen in the directory, would be reported to contain 105 characters.
This discrepancy occurs because when we attempt to write a “\n” to the file using fputs( ), fputs( ) converts the \n to \r\n combination. Here \r stands for carriage return and \n for linefeed. If we read the same line back using fgets( ) the reverse conversion happens. Thus when we write the first line of the poem and a “\n” using two calls to fputs( ), what gets written to the file is
Shining and bright, they are forever,\r\n
When the same line is read back into the array s[ ] using fgets( ), the array contains
Shining and bright, they are forever,\n\0
Thus conversion of \n to \r\n during writing and \r\n conversion to \n during reading is a feature of the standard library functions and not that of the OS. Hence the OS counts \r and \n as separate characters. In our poem there are four lines, therefore there is a discrepancy of four characters (105 - 101).
This discrepancy occurs because when we attempt to write a “\n” to the file using fputs( ), fputs( ) converts the \n to \r\n combination. Here \r stands for carriage return and \n for linefeed. If we read the same line back using fgets( ) the reverse conversion happens. Thus when we write the first line of the poem and a “\n” using two calls to fputs( ), what gets written to the file is
Shining and bright, they are forever,\r\n
When the same line is read back into the array s[ ] using fgets( ), the array contains
Shining and bright, they are forever,\n\0
Thus conversion of \n to \r\n during writing and \r\n conversion to \n during reading is a feature of the standard library functions and not that of the OS. Hence the OS counts \r and \n as separate characters. In our poem there are four lines, therefore there is a discrepancy of four characters (105 - 101).
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