user556761
user556761

Reputation: 261

reading a string from a file

I have one text file. I have to read one string from the text file. I am using c code. can any body help ?

Upvotes: 6

Views: 134843

Answers (4)

Manthan Solanki
Manthan Solanki

Reputation: 53

This is a Simple way to get the string from file.

#include<stdio.h>
#include<stdlib.h>
#define SIZE 2048
int main(){
char read_el[SIZE];
FILE *fp=fopen("Sample.txt", "r");

if(fp == NULL){
    printf("File Opening Error!!");

}
while (fgets(read_el, SIZE, fp) != NULL)
    printf(" %s ", read_el);
fclose(fp);
return 0;
}

Upvotes: 4

Pablo Santa Cruz
Pablo Santa Cruz

Reputation: 181270

Use fgets to read string from files in C.

Something like:

#include <stdio.h>

#define BUZZ_SIZE 1024

int main(int argc, char **argv)
{
    char buff[BUZZ_SIZE];
    FILE *f = fopen("f.txt", "r");
    fgets(buff, BUZZ_SIZE, f);
    printf("String read: %s\n", buff);
    fclose(f);
    return 0;
}

Security checks avoided for simplicity.

Upvotes: 20

Shebin
Shebin

Reputation: 3468

void read_file(char string[60])
{
  FILE *fp;
  char filename[20];
  printf("File to open: \n", &filename );
  gets(filename);
  fp = fopen(filename, "r");  /* open file for input */

  if (fp)  /* If no error occurred while opening file */
  {           /* input the data from the file. */
    fgets(string, 60, fp); /* read the name from the file */
    string[strlen(string)] = '\0';
    printf("The name read from the file is %s.\n", string );
  }
  else          /* If error occurred, display message. */
  {
    printf("An error occurred while opening the file.\n");
  }
  fclose(fp);  /* close the input file */
}

Upvotes: 5

unwind
unwind

Reputation: 399703

This should work, it will read a whole line (it's not quite clear what you mean by "string"):

#include <stdio.h>
#include <stdlib.h>

int read_line(FILE *in, char *buffer, size_t max)
{
  return fgets(buffer, max, in) == buffer;
}

int main(void)
{
  FILE *in;
  if((in = fopen("foo.txt", "rt")) != NULL)
  {
    char line[256];

    if(read_line(in, line, sizeof line))
      printf("read '%s' OK", line);
    else
      printf("read error\n");
    fclose(in);
  }
  return EXIT_SUCCESS;
}

The return value is 1 if all went well, 0 on error.

Since this uses a plain fgets(), it will retain the '\n' line feed at the end of the line (if present).

Upvotes: 5

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