[Rd] Possible bug in read.fwf (PR#7350)

[mase at is.titech.ac.jp]

Full_Name: Shigeru Mase
Version: R 1.9.1 and 2.0.0
OS: Debian Linux
Submission from: (NULL) (219.35.150.115)


I tried to read the following text file "test.txt" with 5 lines using 
read.fwf() function:

# comment 1
1234567   # comment 2
1 234567  # comment 3
12345  67 # comment 4
# comment 5

In R 1.9.1, I got the following result (since I have R 2.0.0 installed now 
I cannot reproduce it now but, at least, my former record says so):

> (x <- read.fwf("test.txt", width=c(2,2,3), skip=1, n=4))
   V1 V2  V3
 1 12 34 567
 2  1 23 456
 3 12 34   5

But, in R 2.0.0, the above command seems to run into endless loop, giving no
response. On the other hand, 

> (x <- read.fwf("test.txt", width=c(2,2,3), skip=1))
  V1 V2  V3
1  1 23 456   # skipped first 2 lines
2 12 34   5   # skipped the last comment line

By the way, the following gave the intended result, but skip the last
comment line:

> (x <- read.fwf("test.txt", width=c(2,2,3), skip=0))
  V1 V2  V3
1 12 34 567
2  1 23 456
3 12 34   5

I have been puzzled and, seemingly, I could not find particular indications
of relevent changes in the help document. I searched relevent bug reports on
this site but seems there are none. I got the same behaviour report from a user
of R 2.0.0 under MS Windows XP.