Re: reading line by line from file

CBFalconer <cbfalconer@xxxxxxxxx> writes:
"Vladimir S. Oka" wrote:
CBFalconer opined:
"Vladimir S. Oka" wrote:
plmanikandan@xxxxxxxxx wrote:

I need to read a file line by line.each line contains different
number of characters.I opened file using fopen function.is there
any function to read the file line by line

Look up `fgets()`.

Among others. Possibly the most convenient is ggets, which is
non-standard, but written in standard C, and available at:

<http://cbfalconer.home.att.net/download/ggets.zip>

Plugging your wares again? ;-)

Good! Anything to get world rid of getses!

Yup. I put it out there in the public domain almost four years
ago, and have had no reports of bugs with it. Some people dislike
the linear buffer increase, but I consider that optimum for the
normal use in interactive input.

I do have one small quibble. Since it quietly strips the newline
character from the input line, there's no good way to tell whether the
last line of an input file had a trailing newline in the first place
(for systems that don't require one).

It's not a huge deal, and it's probably ok as a default behavior, but
it might be nice to have an alternative interface that handles this --
perhaps a second function that leaves the '\n' in place.

<OT>
I like Perl's behavior in this area, but it may not translate well to
C. In Perl, reading a line gives you a string that includes the
trailing newline character; the "chomp" function deletes it. Perl's
strings are variable-length, and are represented in such a way that
"chomp" doesn't have to scan to find the end of the string.
Duplicating this behavior in C might require too much scaffolding,
e.g., returning a structure with additional information rather than
just returning a pointer to a string.
</OT>

--
Keith Thompson (The_Other_Keith) kst-u@xxxxxxx <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <*> <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.
.

Relevant Pages

  • Re: reading line by line from file
    ... reading a line gives you a string that includes the ... trailing newline character; the "chomp" function deletes it. ...
    (comp.lang.c)
  • Re: equivalent of chomp in perl
    ... on Perl, comparable to K&R). ... chomp VARIABLE ... string that doesn't end in a newline. ... char *s; ...
    (comp.lang.c)
  • Re: equivalent of chomp in perl
    ... chomp VARIABLE ... string that doesn't end in a newline. ... and not just any last character. ... char *s; ...
    (comp.lang.c)
  • Re: equivalent of chomp in perl
    ... on Perl, comparable to K&R). ... chomp VARIABLE ... string that doesn't end in a newline. ... and not just any last character. ...
    (comp.lang.c)
  • Re: fscanf reading lines
    ... If you are trying to read the last blank-delimited string: ... replace trailing newline with '\0' ... if ptr!= null, ++ptr points to the beginning of the desired string ... Boeing Associate Technical Fellow ...
    (comp.lang.c)