C File Input/output - Constants

Constants

Constants defined in the stdio.h header include:

Name	Notes
`EOF`	a negative integer of type `int` used to indicate end-of-file conditions
`BUFSIZ`	an integer which is the size of the buffer used by the `setbuf` function
`FILENAME_MAX`	the size of a `char` array which is large enough to store the name of any file that can be opened
`FOPEN_MAX`	the number of files that may be open simultaneously; will be at least 8
`_IOFBF`	an abbreviation for "input/output fully buffered"; it is an integer which may be passed to the `setvbuf` function to request block buffered input and output for an open stream
`_IOLBF`	an abbreviation for "input/output line buffered"; it is an integer which may be passed to the `setvbuf` function to request line buffered input and output for an open stream
`_IONBF`	an abbreviation for "input/output not buffered"; it is an integer which may be passed to the `setvbuf` function to request unbuffered input and output for an open stream
`L_tmpnam`	the size of a `char` array which is large enough to store a temporary filename generated by the `tmpnam` function
`NULL`	a macro expanding to the null pointer constant; that is, a constant representing a pointer value which is guaranteed not to be a valid address of an object in memory
`SEEK_CUR`	an integer which may be passed to the `fseek` function to request positioning relative to the current file position
`SEEK_END`	an integer which may be passed to the `fseek` function to request positioning relative to the end of the file
`SEEK_SET`	an integer which may be passed to the `fseek` function to request positioning relative to the beginning of the file
`TMP_MAX`	the maximum number of unique filenames generable by the `tmpnam` function; will be at least 25

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