C read line as string

Question

char *word[128];
fgets(word, 128, stdin);
if(word == "hello")
    printf("You entered hello as your word.");

So basically I am trying to get user input as a string and then use the following comparison so see if the string the user entered is equal to "hello". however, when compiling this code, it doesn't work. What did I do wrong?

EDIT: So based on feedback so far this is what I have:

char word[128];
fgets(word, 128, stdin);
if(strcmp(word, "Hello") == 0)
     printf("match\n");

However, when I compile and run this program and enter Hello it does not print "match".

`==` is not how string comparisons are done in C. Use [`strcmp`](http://linux.die.net/man/3/strcmp). — kaylum, Feb 10 '16 at 02:54
[How do I properly compare strings in C?](https://stackoverflow.com/questions/8004237/how-do-i-properly-compare-strings-in-c) — kaylum, Feb 10 '16 at 02:56
If you learn how to *hard-code* and *print* strings, you can separate the two functions (getting user input and comparing strings) and tackle them independently. — Beta, Feb 10 '16 at 02:56
Is me needing to use strcmp the only thing that is wrong with the above code? Is the string defined properly and would fgets work in this case with how the string is defined? — Jason Rigley, Feb 10 '16 at 02:56
`char *word[128]` should be `char word[128]`. That plus `strcmp` should work. — kaylum, Feb 10 '16 at 02:57
Kaylum could you please look at the edit I did to the question — Jason Rigley, Feb 10 '16 at 03:08
Always read carefully the man pages for the functions you use. From the [`fgets` man page](http://linux.die.net/man/3/fgets): "If a newline is read, it is stored into the buffer." That is, `word` contains a newline character and hence it is not a match. — kaylum, Feb 10 '16 at 03:10

Ely · Answer 1 · 2016-02-10T03:17:32.460

Use strcmp(char *s1, char *s2) to compare strings. Also change char *wordto char word[].

fgets, as you used it, reads in characters from stdin until it has read new line, 127 characters or EOF (end of file). The new line is part of the string read in word and so the comparison is not equal.

To illustrate, you need to know that a C-style string is an array of characters ended by the special escape character \0. So you are comparing those two strings hello\n\0 and hello\0; note the newline character in the string read from stdin.

You can overwrite the \n at the 6th position with \0 so your strings compare to equal.
A better, general solution is to simply iterate over the characters of the string and replace the first found \n by \0; this could be a good exercise for you maybe.

== does not compare the strings the way you expect it. It merely compares the addresses of the two objects, which in this case are of course different.

score 0 · Answer 2 · answered Feb 10 '16 at 02:56

0

You need to use strcmp to compare strings.

if(strcmp(word, "Hello") == 0)
  printf("match\n");

answered Feb 10 '16 at 02:56

Umamahesh P

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C read line as string

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