Thread: Simple strings

How to i check a string to see if another string is inside it.
eg.

string1: "folder1\folder2\folder3\mytext.txt
string2: "mytext.txt"

How do see if string2 is present in string 1

thankyou

char *str1 = "folder1\folder2\folder3\mytext.txt", *str2 = "mytext.txt";

char *buffer = strstr( str1, str2 );
if( !strcmp( buffer, str2 ) )
puts( "string occurs :-)" );

didn't compile it, but should work. note that we can compare buffer and str2 only, if the searched string is in the end of str1.

Originally posted by Unregistered
char *str1 = "folder1\folder2\folder3\mytext.txt", *str2 = "mytext.txt";

char *buffer = strstr( str1, str2 );
if( !strcmp( buffer, str2 ) )
puts( "string occurs :-)" );

didn't compile it, but should work. note that we can compare buffer and str2 only, if the searched string is in the end of str1.

Close but no cigar. I'd prefer...

Code:

char * buf= strstr(str1,str2);
if (buf) {
  /* it's in there */
} else {
  /* it isn't */
}

Ian Woods

The situation is that, i will be passing a command line argument into the program (using argv[]) from unix and if the word 'encode' is passed into it then it will perform an encode function ive done or if the word decode is passed into the program it will do a decode function.

cheers

Originally posted by jackwoz
The situation is that, i will be passing a command line argument into the program (using argv[]) from unix and if the word 'encode' is passed into it then it will perform an encode function ive done or if the word decode is passed into the program it will do a decode function.

cheers

This is a different situation to your original post. Assuming you want your command line something like this...

myprog encode myfile

then you can just strcmp with argv[1] (since argv has been split based on the white space). So, you could imagine something like this:

Code:

int main(int argc, char ** argv) {
  if (argc!=3) {
    /* show help message */
    return EXIT_FAILURE;
  }

  if (!strcmp(argv[1],"encode")) {
    /* do some encoding */
  } else if (!strcmp(argv[1],"decode")) {
    /* do some decoding */
  } else {
    /* it was neither encode or decode, so make an error message */
  }

...

Ian Woods

Cheers Ian.I seemed to have got things confused in my head.