I have fscanf to read lines of setting from a configuration file. Those settings have strictly predefined format which looks like
name1=option1;
name2=option2;
...
so basically I do
fscanf(configuration,"%[^=]=%[^;];",name,option);
where configuration is the file stream and name and option are programming buffers.
The problem is that the name buffer contains a newline character I don't want. Is there format specifier I've missed in the "[^...]" set to skip newline character? Anyway, can it be solved through format specifier ever?
BTW: Swallowing the newline character by writting this
"%[^=]=%[^;];\n"
is not elegent I think for that the newline character could repeat more than once anywhere.
fscanf type specifiers String of characters. This will read subsequent characters until a whitespace is found (whitespace characters are considered to be blank, newline and tab).
fscanf() is a very clunky interface for parsing files, it treats spaces, newlines and other whitespace characters the same, except for the %c and the %[ conversion specifiers.
Use scanf(" %c", &c2); . This will solve your problem.
The fgets() function stores the result in string and adds a NULL character (\0) to the end of the string. The string includes the newline character, if read.
Just add space at the end of the format string:
"%[^=]=%[^;]; "
This will eat all whitespace characters, including new-lines.
Quotation from cplusplus.com:
Whitespace character: the function will read and ignore any whitespace characters encountered before the next non-whitespace character (whitespace characters include spaces, newline and tab characters -- see isspace). A single whitespace in the format string validates any quantity of whitespace characters extracted from the stream (including none).
An alternative is to use fgets()
to read the entire line into a string, then use sscanf()
. This has an advantage in debugging in that you can see exactly what data the function is working on.
This will work:
fscanf(configuration,"%[^=]=%[^;];%[^\n]",name,option,dummy);
You will have to consume the new line character.Otherwise,the newline is left in the input stream.
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