Gitly


1 import os
2 import time
3 
4 if os.args.len == 1 {
5     eprintln('A small `tail -f file` like program, written in V.')
6     eprintln('Usage: `v run examples/vtail.v your_long_file.log`')
7     exit(0)
8 }
9 
10 tfile := os.args[1] or { panic('pass 1 file path as argument') }
11 mut f := os.open_file(tfile, 'r') or { panic('file ${tfile} does not exist') }
12 f.seek(0, .end)!
13 mut read_pos := f.tell()!
14 mut buf := []u8{len: 10 * 1024}
15 for {
16     bytes := f.read_bytes_with_newline(mut buf)!
17     if bytes == 0 && f.eof() {
18         // The end of the file has been reached, so wait a bit, and retry from the same position:
19         f.close()
20         time.sleep(500 * time.millisecond)
21         f = os.open_file(tfile, 'r')!
22         f.seek(read_pos, .start)!
23         continue
24     }
25     read_pos += bytes
26     print(unsafe { (&u8(buf.data)).vstring_with_len(bytes) })
27 }
28

1	import os
2	import time
3
4	if os.args.len == 1 {
5	eprintln('A small `tail -f file` like program, written in V.')
6	eprintln('Usage: `v run examples/vtail.v your_long_file.log`')
7	exit(0)
8	}
9
10	tfile := os.args[1] or { panic('pass 1 file path as argument') }
11	mut f := os.open_file(tfile, 'r') or { panic('file ${tfile} does not exist') }
12	f.seek(0, .end)!
13	mut read_pos := f.tell()!
14	mut buf := []u8{len: 10 * 1024}
15	for {
16	bytes := f.read_bytes_with_newline(mut buf)!
17	if bytes == 0 && f.eof() {
18	// The end of the file has been reached, so wait a bit, and retry from the same position:
19	f.close()
20	time.sleep(500 * time.millisecond)
21	f = os.open_file(tfile, 'r')!
22	f.seek(read_pos, .start)!
23	continue
24	}
25	read_pos += bytes
26	print(unsafe { (&u8(buf.data)).vstring_with_len(bytes) })
27	}
28