File processing

eThe term "elementary", as used below, refers to all I/O functions that work on the basis of file descriptors, as opposed to the standard I/O functions, which work on the basis of file pointers. In addition, functions that can also be used on files with record-oriented input/output (record I/O) are indicated as such.

File access (open, close, position)

Name	Brief description
close	Close file and flush buffer (elementary, also record I/O)
creat	Create file or overwrite existing file (elementary, also record I/O)
creat64	64-bit variant of creat for processing large files (> 2 GB, also record I/O)
fclose	Close file and flush buffer (also record I/O)
fdelrec	Delete record in indexed-sequential file (record I/O only)
fdopen	Assign a file pointer to a file descriptor
fflush	Flush file buffer
fgetpos	Return current position of the read/write pointer (also record I/O)
fgetpos64	64-bit variant of fgetpos for processing large files (> 2 GB)
flocate	Explicitly position indexed-sequential file (record I/O only)
fopen	Open file (also record I/O)
fopen64	64-bit variant of fopen for processing large files (> 2 GB, also record I/O)
freopen	Reassign file pointer (also record I/O)
freopen64	64-bit variant of freopen for processing large files (> 2 GB, also record I/O)
fseek	Position read/write pointer (also record I/O)
fseek64	64-bit variant of fseek for processing large files (> 2 GB, also record I/O)
fsetpos	Position read/write pointer (also record I/O)
fsetpos64	64-bit variant of fsetpos for processing large files (> 2 GB, also record I/O)
ftell	Determine current position of the read/write pointer
ftell64	64-bit variant of ftell for processing large files (> 2 GB)
lseek	Position read/write pointer (elementary, also record I/O)
lseek64	64-bit variant of lseek for processing large files (> 2 GB, also record I/O)
fwide	Query/define orientation of a file
open	Open file (elementary, also record I/O)
open64	64-bit variant of open for processing large files (> 2 GB, also record I/O)
rewind	Position read/write pointer to beginning of file (also record I/O)
setbuf	Set up input/output buffer
setvbuf	Set up input/output buffer
tell	Query current position of the read/write pointer (elementary)

File management

Name	Brief description
bs2fstat	Access file name from catalog
mktemp	Generate unique temporary file name
remove	Delete file (also record I/O)
rename	Rename file (also record I/O)
tmpfile	Open temporary binary file
tmpfile64	64-bit variant of tmpfile for processing large files (>2 GB)
tmpnam	Generate temporary file name
unlink	Erase file (also record I/O)

File and error information

Name	Brief description
clearerr	Delete end-of-file and error flag (also record I/O)
feof	Test for end of file (also record I/O)
ferror	Test for file error (also record I/O)

Input/output

Name	Brief description
fgetc	Read a character from a file
fgets	Read a string from a file
fgetwc	Read a wide character from input file
fgetws	Read a wide character string from a file
fprintf	Formatted output to a file
fputc	Write a character to a file
fputs	Write a string to a file
fputwc	Write a wide character to a file
fputws	Write a wide character string to a file
fread	Read blockwise from a file (also record I/O)
fscanf	Formatted input from a file
fwprintf	Write a formatted character to an output file (wide character format)
fwrite	Write blockwise to a file (also record I/O)
fwscanf	Formatted input from a file (wide character format)
getc	Read a character from a file
getchar	Read a character from standard input
gets	Read a string from standard input
getw	Read wordwise from a file
getwc	Read a wide character from a file
getwchar	Read a wide character from standard input
printf	Formatted output to standard output
putc	Write a character to a file
putchar	Output a character to standard output
puts	Output a string to standard output
putw	Write wordwise to a file
putwc	Write a wide character to a file
putwchar	Write wide characters to standard output
read	Read from a file (elementary, also record I/O)
scanf	Formatted input from standard input
snprintf	Formatted output to a string
sprintf	Formatted output to a string
sscanf	Formatted input from a string
swprintf	Formatted output to a wide character string
swscanf	Formatted input from a wide character string
ungetc	Put a character back in the buffer
ungetwc	Put a wide character back in the buffer
vfprintf	Formatted output to a file
vfwprintf	Write a formatted character to a file (wide character format)
vfwscanf	Formatted input from a file (wide character format)
vprintf	Formatted output to standard output
vsnprintf	Formatted output to character string
vsprintf	Formatted output to character string
vswprintf	Write a formatted character to a wide character string
vswscanf	Formatted input from a wide character string
vwprintf	Formatted output to standard output (wide character format)
vwscanf	Formatted input from standard input (wide character format)
wprintf	Formatted output to standard output (wide character format)
write	Write to a file (elementary, also record I/O)
wscanf	Formatted input from standard input (wide character format)