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GETLINE(3) FreeBSD Library Functions Manual GETLINE(3)
NAME getdelim, getline - get a line from a stream
LIBRARY Standard C Library (libc, -lc)
SYNOPSIS #include <stdio.h>
ssize_t getdelim(char ** restrict linep, size_t * restrict linecapp, int delimiter, FILE * restrict stream);
ssize_t getline(char ** restrict linep, size_t * restrict linecapp, FILE * restrict stream);
DESCRIPTION The getdelim() function reads a line from stream, delimited by the character delimiter. The getline() function is equivalent to getdelim() with the newline character as the delimiter. The delimiter character is included as part of the line, unless the end of the file is reached.
The caller may provide a pointer to a malloced buffer for the line in *linep, and the capacity of that buffer in *linecapp. These functions expand the buffer as needed, as if via realloc(). If linep points to a NULL pointer, a new buffer will be allocated. In either case, *linep and *linecapp will be updated accordingly.
RETURN VALUES The getdelim() and getline() functions return the number of characters stored in the buffer, excluding the terminating NUL character. The value -1 is returned if an error occurs, or if end-of-file is reached.
EXAMPLES The following code fragment reads lines from a file and writes them to standard output. The fwrite() function is used in case the line contains embedded NUL characters.
char *line = NULL; size_t linecap = 0; ssize_t linelen; while ((linelen = getline(&line, &linecap, fp)) > 0) fwrite(line, linelen, 1, stdout); free(line);
ERRORS These functions may fail if:
[EINVAL] Either linep or linecapp is NULL.
[EOVERFLOW] No delimiter was found in the first SSIZE_MAX characters.
These functions may also fail due to any of the errors specified for fgets() and malloc().
HISTORY These routines first appeared in FreeBSD 8.0.
BUGS There are no wide character versions of getdelim() or getline().
FreeBSD 14.0-RELEASE-p11 July 30, 2016 FreeBSD 14.0-RELEASE-p11