ARM Compiler toolchain v4.1 for µVision Using the Compiler

Compiler Coding Practices
5.80 snprintf family of functions in C99
Using the sprintf family of functions found in the C90 standard header can be
dangerous. In the statement:
sprintf(buffer, size, "Error %d: Cannot open file '%s'", errno, filename);
the variable size specifies the minimum number of characters to be inserted into buffer.
Consequently, more characters can be output than might fit in the memory allocated to the
string.
The snprintf functions found in the C99 version of are safe versions of the sprintf
functions that prevent buffer overrun. In the statement:
snprintf(buffer, size, "Error %d: Cannot open file '%s'", errno, filename);
the variable size specifies the maximum number of characters that can be inserted into buffer.
The buffer can never be overrun, provided its size is always greater than the size specified by
size.
5.80.1 See also
Concepts
• New library features of C99 on page 5-79.
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