Hi,
Could anyone please suggest me a way to read parts from a tab -delimted file i.e. I want to read data of the 3rd and the 5th columns?
if my data is:
1234 \t 2342 \t qwert \t iuy1 \t hgy7
2323 \t 2323 \t fghjj \t sdsds \t dwe3
.
.
.
I want to read :
str A =" qwert"
and
str B = "hg7y"
Thanks,
AK
The usual suspects: fgets + sscanf. A skeleton might be as follows.
Code:#include <stdio.h> int main(void) { static const char filename[] = "file.txt"; FILE *file = fopen(filename, "r"); if ( file != NULL ) { char line[BUFSIZ]; while ( fgets(line, sizeof line, file) != NULL ) { char s[20]; if ( sscanf(line, "%*s %*s %19s", s) == 1 ) { puts(s); } } } else { perror(filename); } return 0; } /* my output qwert fghjj */
7. It is easier to write an incorrect program than understand a correct one.
40. There are two ways to write error-free programs; only the third one works.*
I'll be obliged if you can explain the sscanf line. how is it handling the two columns? what if there were 3 columns, say 1,3 and 5?
http://web.archive.org/web/200502070...t.html#4.9.6.2
[edit]Code:#include <stdio.h> int main(void) { static const char filename[] = "file.txt"; FILE *file = fopen(filename, "r"); if ( file != NULL ) { char line[BUFSIZ]; while ( fgets(line, sizeof line, file) != NULL ) { char one[20], three[22], five[18]; if ( sscanf(line, "%19s %*s %21s %*s %17s", one, three, five) == 3 ) { printf("one = \"%s\", three = \"%s\", five = \"%s\"\n", one, three, five); } } } else { perror(filename); } return 0; } /* my output one = "1234", three = "qwert", five = "hgy7" one = "2323", three = "fghjj", five = "dwe3" */
Last edited by Dave_Sinkula; 01-23-2006 at 11:29 PM.
7. It is easier to write an incorrect program than understand a correct one.
40. There are two ways to write error-free programs; only the third one works.*
got u... u rock...
Also, if I've a file which have first 4 lines which I don't want to read, how can I move the pointer to the 5th line to start reading?
Is using 4 fgets a good idea?
AK
Perhaps use fgets in a loop to read (and discard) the number of lines you enter a loop with those that you do care about.
7. It is easier to write an incorrect program than understand a correct one.
40. There are two ways to write error-free programs; only the third one works.*
But I think there is some problem with it. I use:
and it puts only the 1st line. Is there any way of flushing c?Code:char c[120]; for (i=0;i<4;i++){ fgets (c,120,fp); puts(c); }
(edited) Try fflush(NULL) ... it should flush all open streams.
Last edited by eerok; 01-24-2006 at 10:40 PM.
