ambiguity in program output


 
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# 1  
Old 01-21-2008
ambiguity in program output

1 #include <fcntl.h>
2
3 main(int argc, char *argv[])
4 {
5 char buf[1];
6 int fd, count = 0;
7
8 if (argc > 1)
9 fd = open(argv[1], O_RDONLY);
10 else
11 fd = 0; /* Use standard input */
12
13 while (read(fd, buf, 1) > 0) {
14 if (count < 5) write(1, buf, 1);
15 if (buf[0] == '\n') count++;
16 }
17 }

Here buf can store only one character.
But if i run it as:-

"prog_name /etc/passwd" how does it give first five lines.
# 2  
Old 01-21-2008
Sorry for bothering anyone if read it.
Got the answer.

read() function reads an entire line from input, i was thinking it of as a character.

Thanks
bishweshwar
# 3  
Old 01-21-2008
Please use CODE tags Smilie ,

its quite difficult to read through the code without them.

It seems that the code is pasted from editor with line numbers set
# 4  
Old 01-21-2008
man fgets.
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