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@(#)getc.3 8.1 (Berkeley) 6/4/93
$FreeBSD$

.Dd April 4, 2020 .Dt GETC 3 .Os .Sh NAME .Nm fgetc , .Nm getc , .Nm getc_unlocked , .Nm getchar , .Nm getchar_unlocked , .Nm getw .Nd get next character or word from input stream .Sh LIBRARY .Lb libc .Sh SYNOPSIS n stdio.h .Ft int .Fn fgetc "FILE *stream" .Ft int .Fn getc "FILE *stream" .Ft int .Fn getc_unlocked "FILE *stream" .Ft int .Fn getchar void .Ft int .Fn getchar_unlocked void .Ft int .Fn getw "FILE *stream" .Sh DESCRIPTION The .Fn fgetc function obtains the next input character (if present) from the stream pointed at by .Fa stream , or the next character pushed back on the stream via .Xr ungetc 3 .

p The .Fn getc function acts essentially identically to .Fn fgetc , but is a macro that expands in-line.

p The .Fn getchar function is equivalent to .Fn getc stdin .

p The .Fn getw function obtains the next .Vt int (if present) from the stream pointed at by .Fa stream .

p The .Fn getc_unlocked and .Fn getchar_unlocked functions are equivalent to .Fn getc and .Fn getchar respectively, except that the caller is responsible for locking the stream with .Xr flockfile 3 before calling them. These functions may be used to avoid the overhead of locking the stream for each character, and to avoid input being dispersed among multiple threads reading from the same stream. .Sh RETURN VALUES If successful, these routines return the next requested object from the .Fa stream . Character values are returned as an .Vt "unsigned char" converted to an .Vt int . If the stream is at end-of-file or a read error occurs, the routines return .Dv EOF . The routines .Xr feof 3 and .Xr ferror 3 must be used to distinguish between end-of-file and error. If an error occurs, the global variable .Va errno is set to indicate the error. The end-of-file condition is remembered, even on a terminal, and all subsequent attempts to read will return .Dv EOF until the condition is cleared with .Xr clearerr 3 . .Sh SEE ALSO .Xr ferror 3 , .Xr flockfile 3 , .Xr fopen 3 , .Xr fread 3 , .Xr getwc 3 , .Xr putc 3 , .Xr ungetc 3 .Sh STANDARDS The .Fn fgetc , .Fn getc , and .Fn getchar functions conform to .St -isoC . The .Fn getc_unlocked and .Fn getchar_unlocked functions conform to .St -p1003.1-2001 . .Sh HISTORY The .Fn getc and .Fn getw functions appeared in a similar form in .At v1 ; and were integrated into stdio in .At v7 ; .Fn getchar in .At v4 ; and .Fn fgetc in .At v7 . .Sh BUGS Since .Dv EOF is a valid integer value, .Xr feof 3 and .Xr ferror 3 must be used to check for failure after calling .Fn getw . The size and byte order of an .Vt int varies from one machine to another, and .Fn getw is not recommended for portable applications.