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man pages section 3: Library Interfaces and Headers

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Updated: Thursday, June 13, 2019
 
 

stdio.h(3HEAD)

Name

stdio.h, stdio - standard buffered input/output

Synopsis

#include <stdio.h>

Description

The <stdio.h> header defines the following macros as positive integer constant expressions:

BUFSIZ

size of <stdio.h> buffers

_IOFBF

input/output fully buffered

_IOLBF

input/output line buffered

_IONBF

input/output unbuffered

L_ctermid

maximum size of character array to hold ctermid() output

L_tmpnam

maximum size of character array to hold tmpnam() output

SEEK_CUR

seek relative to current position

SEEK_END

seek relative to end-of-file

SEEK_SET

seek relative to start-of-file

The following macros are defined as positive integer constant expressions that denote implementation limits:

{FILENAME_MAX}

Maximum size in bytes of the longest filename string that the implementation guarantees can be opened.

{FOPEN_MAX}

Number of streams that the implementation guarantees can be open simultaneously. The value is at least eight.

{TMP_MAX}

Minimum number of unique filenames generated by tmpnam(). Maximum number of times an application can call tmpnam() reliably. The value of {TMP_MAX} is at least 25. On XSI-conformant systems, the value of {TMP_MAX} is at least 10000.

The following macro name is defined as a negative integer constant expression:

EOF

end-of-file return value

The following macro name is defined as a null pointer constant:

NULL

null pointer

The following macro name is defined as a string constant:

P_tmpdir

default directory prefix for tempnam()

The following is defined as expressions of type “pointer to FILE” point to the FILE objects associated, respectively, with the standard error, input, and output streams:

stderr

standard error output stream

stdin

standard input stream

stdout

standard output stream

The following data types are defined through typedef:

FILE

structure containing information about a file

fpos_t

non-array type containing all information needed to specify uniquely every position within a file

va_list

as described in <stdarg.h>

size_t

as described in <stddef.h>

Attributes

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE
ATTRIBUTE VALUE
Interface Stability
Committed
Standard

See Also

rename(2), ctermid(3C), fclose(3C), fdopen(3C), fflush(3C), fgetc(3C), fgetpos(3C), fgets(3C), flockfile(3C), fopen(3C), fputc(3C), fputs(3C), fputwc(3C), fread(3C), freopen(3C), fseek(3C), fsetpos(3C), ftell(3C), fwrite(3C), getopt(3C), getwchar(3C), perror(3C), popen(3C), printf(3C), remove(3C), rewind(3C), scanf(3C), setbuf(3C), stdio(3C), system(3C), tmpfile(3C), tmpnam(3C), ungetc(3C), vprintf(3C), attributes(7), standards(7)