replacing string in file except the first

hi everyone
it my first post here
my problem is i want ot replace a string of text
in a file the files are one a one word/one line
bases
i have come this far but i don't seem to get
strstr() to work
would it also be possible to a sort of temp file
in place of asking for the tempfile
i there a way that i can avoid gets()
cause my compiler says that is dangerous
but when i use fgets or scanf i got no result
this my fisrt program ever so be nice
if it looks crappy

Code:

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

#define BUFSIZE 255

int main (void)
{
	char filename[BUFSIZE];
	char tmpname[BUFSIZE];
	char str_search[BUFSIZE];
	char str_replace[BUFSIZE];
	FILE *fp;
	FILE *tmpfp;
	char buffer[BUFSIZE];
	int count = 0, count_lines = 0;
	char *loc;
	int first;
	
	puts("Enter filename to search: ");
	gets(filename);

	puts("Enter tmpfilename");
	gets(tmpname);
	
	puts("Enter string to search: ");
	gets(str_search);

	puts("Enter string to replace");
	gets(str_replace);

	if ((fp = fopen(filename, "rb")) == NULL)
	{
		fprintf(stderr ,"Error opening filename");
		exit(-1);
	}
	if ((tmpfp = fopen(tmpname, "wb")) == NULL)
	{
		fprintf(stderr,"Error opening filename");
		exit(-1);
	}

	while(!feof(fp))
	{
		fgets(buffer,BUFSIZE,fp);
		count++;
	}
	count_lines = count;
	rewind(fp);
	count = 0;
	while(!feof(fp))
	{
		fgets(buffer,BUFSIZE,fp);
		count++;
		if((strstr(buffer, str_search) != NULL))
		{
			first = count;
			break;
		}
	}
	rewind(fp);

	for(count = 0; count < count_lines-1; count++)
	{
		fgets(buffer,BUFSIZE,fp);
		loc = strstr(buffer, str_replace);
		printf("%d\n" , loc-buffer);
		if (loc != NULL && count != count_lines)
		{
		fputs(str_replace, tmpfp);
		}
		else
		{
		fputs(buffer, tmpfp);
		}
	}
	fclose(fp);
	fclose(tmpfp);
	/*rename(tmpname,filename);*/
	return 0;
}

an example of the test file

we
came
here
we
came
here

replace we with they or whatever

thx in advance

thx for your reply
i tried it out
and i am puzzled about two things
fgets( buff, sizeof(buff), stdin ); //this is clear
but this searches through the whole string
for a new string if found replace with end char
for strings
{ char *p = strchr( buff, '\n' ); if ( p != NULL ) *p = '\0'; }
and

Code:

while ( fgets(buffer,BUFSIZE,fp) != NULL ) {
  if ( strstr( buffer, str_search ) != NULL ) {
    if ( !seen_first ) { //could you explan this if statenment i don't get it what suppossed to happen
      // this is the first, just set the flag
      seen_first = 1;
    } else {
      // all other matches
    }
  } else {
    // normal case
  }
}

is there also a way of only using one specified
file by the user bu using a tmpfile
my book says to use tmpname but
again my comiler complains that this is dangerous

thx again for your reply

thx again for your quick reply

the first one i understand now
but when i follow the second piece of code
i got this

Code:

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

#define BUFSIZE 255

int main (void)
{
	char filename[BUFSIZE];
	char tmpname[BUFSIZE];
	char str_search[BUFSIZE];
	char str_replace[BUFSIZE];
	FILE *fp;
	FILE *tmpfp;
	char buffer[BUFSIZE];
	int seen_first = 0;
	
	puts("Enter filename to search: ");
	fgets(filename,sizeof(filename),stdin);
	char *p = strchr( filename, '\n' );
       		if ( p != NULL )
	     		*p = '\0';
	
		
	puts("Enter tmpfile: ");
	fgets(tmpname, sizeof(tmpname), stdin);
	p = strchr( tmpname, '\n' );
       		if ( p != NULL )
	     		*p = '\0';

	puts("Enter string to search: ");
	fgets(str_search,sizeof(str_search),stdin);
	p = strchr( str_search, '\n' );
       		if ( p != NULL )
	     		*p = '\0';
	
	puts("Enter string to replace");
	fgets(str_replace, sizeof(str_replace), stdin);
	p = strchr( str_replace, '\n' );
       		if ( p != NULL )
	     		*p = '\0';
	

	if ((fp = fopen(filename, "r")) == NULL)
	{
		fprintf(stderr ,"Error opening filename");
		exit(-1);
	}
	if ((tmpfp = fopen(tmpname, "w")) == NULL)
	{
		fprintf(stderr,"Error opening filename");
		exit(-1);
	}

	while(fgets(buffer,BUFSIZE,fp) != NULL);
	{
		if(strstr(buffer, str_search) != NULL)
		{
			if (!seen_first)
			{
			fputs(buffer, tmpfp);
			seen_first = 1;
			}
			else
			{
			fputs(str_replace, tmpfp);
			}
		}
		else
		{
		fputs(buffer, tmpfp);
		}
	}
	fclose(fp);
	fclose(tmpfp);
	/*rename(tmpname,filename);*/
	return 0;
}

result
only the last line is in the file that
i specified as tmpfile
when i
replace

Code:

	puts("Enter tmpfile: ");
	fgets(tmpname, sizeof(tmpname), stdin);
	p = strchr( tmpname, '\n' );
       		if ( p != NULL )
	     		*p = '\0'

with
tmpname(tmpname);
i get the following messages
tmp/ccDoSU1B.o: In function `main':
/tmp/ccDoSU1B.o(.text+0x179): the use of `tmpnam' is dangerous, better use `mkstemp'

thx again for your help

thx again for the quick reply
ok i am getting nearer

file to search
we
came
here
we
came
here
we
came
here

out put file
we
came
here
theycame
here
theycame
here

have you got any idea's
on how this comes

i didn't kwow that about the var
will check the book again
never tried c++(and i think i will keep it with c
for the moment (define moment a year of two))

i will experiment with tmp functions
is it a problem reading and writing to
binary files when it is a text file
is a text file not also a binary file in a way

thx again

alreagy got it
replaced
[code]
puts("Enter string to replace");
fgets(str_replace, sizeof(str_replace), stdin);
p = strchr( str_replace, '\n' );
if ( p != NULL )
*p = '\0';

[\cpde]
puts("Enter string to replace");
fgets(str_replace, sizeof(str_replace), stdin);

question is this save??????