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_getc_nolock, _getwc_nolock

Reads a character from a stream.

int _getc_nolock( 
   FILE *stream 
);
wint_t _getwc_nolock( 
   FILE *stream 
);

Parameters

  • stream
    Input stream.

Return Value

See getc, getwc.

Remarks

These functions are identical to getc and getwc except that they do not lock the calling thread. They might be faster because they do not incur the overhead of locking out other threads. Use these functions only in thread-safe contexts such as single-threaded applications or where the calling scope already handles thread isolation.

Generic-Text Routine Mappings

Tchar.h routine

_UNICODE and _MBCS not defined

_MBCS defined

_UNICODE defined

_gettc_nolock

getc_nolock

getc_nolock

getwc_nolock

Requirements

Routine

Required header

getc_nolock

<stdio.h>

getwc_nolock

<stdio.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

Example

// crt_getc_nolock.c
// Use getc to read a line from a file.

#include <stdio.h>

int main()
{
    char buffer[81];
    int i, ch;
    FILE* fp;
    
    // Read a single line from the file "crt_getc_nolock.txt".
    fopen_s(&fp, "crt_getc_nolock.txt", "r");
    if (!fp)
    {
       printf("Failed to open file crt_getc_nolock.txt.\n");
       exit(1);
    }

    for (i = 0; (i < 80) && ((ch = getc(fp)) != EOF)
                         && (ch != '\n'); i++)
    {
        buffer[i] = (char) ch;
    }
       
    // Terminate string with a null character 
    buffer[i] = '\0';
    printf( "Input was: %s\n", buffer);

    fclose(fp);
}

Input: crt_getc_nolock.txt

Line the first.
Line the second.

Output

Input was: Line the first.

.NET Framework Equivalent

See Also

Concepts

Stream I/O

fgetc, fgetwc

_getch, _getwch

putc, putwc

ungetc, ungetwc