Editing C file input/output (section)

===Constants===
Constants defined in the {{mono|<stdio.h>}} header include:

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! Name !! Notes
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! style="font-family:monospace" | [[End-of-file|EOF]]
| A negative integer of type {{mono|int}} used to indicate end-of-file conditions
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! style="font-family:monospace" | {{Anchor|BUFSIZ}} [http://c-p-p.net/c/stdio.h/bufsiz BUFSIZ]
| An integer which is the size of the buffer used by the {{mono|setbuf()}} function
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! style="font-family:monospace" | FILENAME_MAX
| The size of a {{mono|char}} array which is large enough to store the name of any file that can be opened
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! style="font-family:monospace" | FOPEN_MAX
| The number of files that may be open simultaneously; will be at least eight
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! style="font-family:monospace" | _IOFBF
| An abbreviation for "input/output fully buffered"; it is an integer which may be passed to the {{mono|setvbuf()}} function to request ''block buffered'' input and output for an open stream
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! style="font-family:monospace" | _IOLBF
| An abbreviation for "input/output line buffered"; it is an integer which may be passed to the {{mono|setvbuf()}} function to request ''line buffered'' input and output for an open stream
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! style="font-family:monospace" | _IONBF
| An abbreviation for "input/output not buffered"; it is an integer which may be passed to the {{mono|setvbuf()}} function to request ''unbuffered'' input and output for an open stream
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! style="font-family:monospace" | L_tmpnam
| The size of a {{mono|char}} array which is large enough to store a temporary filename generated by the {{mono|tmpnam()}} function
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! style="font-family:monospace" | 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
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! style="font-family:monospace" | SEEK_CUR
| An integer which may be passed to the {{mono|fseek()}} function to request positioning relative to the current file position
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! style="font-family:monospace" | SEEK_END
| An integer which may be passed to the {{mono|fseek()}} function to request positioning relative to the end of the file
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! style="font-family:monospace" | SEEK_SET
| An integer which may be passed to the {{mono|fseek()}} function to request positioning relative to the beginning of the file
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! style="font-family:monospace" | TMP_MAX
| The maximum number of unique filenames generable by the {{mono|tmpnam()}} function; will be at least 25
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