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string - Using fopen with input filenames in C

At some point in my code, I want to read a name for a file that I will be creating (and/or editing) and I've come up with the following:

FILE *fp;
char filename[15];
fgets(filename, 15, stdin);
fp = fopen(filename, "a");
fprintf(fp, "some stuff goes here");
fclose(fp);

Even though that does compile and run, it does not create (or open, if I manually create it) the file specified by filename.
What would you suggest?

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by (71.8m points)

fgets() stores the newline character read from stdin after reading a line of input. You need to strip it manually, e.g.

size_t len = strlen(filename);
if (len > 0 && filename[len - 1] == '
')
    filename[len - 1] = '';

You should also check that fopen() doesn't return NULL, which it will do if it was unable to open the file. I think using fprintf with a NULL file pointer is undefined behaviour.


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