Search for strings within a text file

	#include <stdlib.h>
	#include <stdio.h>
	#include <string.h>
	const char email_receive_set_output_high_string[] = {"set_output_high"};
	const char email_receive_set_output_low_string[] = {"set output low"};

	FILE *fp=fopen("/home/pi/myproject/somefile","r");
	char  tmp[1024] = {0x0};
	while(fp != NULL && fgets(tmp, sizeof(tmp), fp) != NULL)		//fgets gets one line at a time, up to the max size - not the next block of max size.  So ensure the size is >= to the max line length within the file to ensure complete lines will be checked.
		if (strstr(tmp, email_receive_set_output_high_string))		//Do lines contain string 
			printf("Setting output high\n");
		if (strstr(tmp, email_receive_set_output_low_string))
			printf("Setting output low\n");
	if(fp != NULL)




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  1. Jake

    7 years ago

    this does not compile:

    error: expected unqualified-id before ‘while’

    is the error message received when I try to compile with code::blocks on my Pi


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