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getline(3) [netbsd man page]

GETDELIM(3)						   BSD Library Functions Manual 					       GETDELIM(3)

getdelim, getline -- read a delimited record from a stream LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <stdio.h> ssize_t getdelim(char ** restrict lineptr, size_t * restrict n, int delimiter, FILE * restrict stream); ssize_t getline(char ** restrict lineptr, size_t * restrict n, FILE * restrict stream); DESCRIPTION
The getdelim() function reads from the stream until it encounters a character matching delimiter, storing the input in *lineptr. The buffer is NUL-terminated and includes the delimiter. The delimiter character must be representable as an unsigned char. If *n is non-zero, then *lineptr must be pre-allocated to at least *n bytes. The buffer should be allocated dynamically; it must be possible to free(3) *lineptr. getdelim() ensures that *lineptr is large enough to hold the input, updating *n to reflect the new size. The getline() function is equivalent to getdelim() with delimiter set to the newline character. RETURN VALUES
The getdelim() and getline() functions return the number of characters read, including the delimiter. If no characters were read and the stream is at end-of-file, the functions return -1. If an error occurs, the functions return -1 and the global variable errno is set to indi- cate the error. The functions do not distinguish between end-of-file and error, and callers must use feof(3) and ferror(3) to determine which occurred. EXAMPLES
The following code fragment reads lines from a file and writes them to standard output. char *line = NULL; size_t linesize = 0; ssize_t linelen; while ((linelen = getline(&line, &linesize, fp)) != -1) fwrite(line, linelen, 1, stdout); if (ferror(fp)) perror("getline"); ERRORS
[EINVAL] lineptr or n is a NULL pointer. [EOVERFLOW] More than SSIZE_MAX characters were read without encountering the delimiter. The getdelim() and getline() functions may also fail and set errno for any of the errors specified in the routines fflush(3), malloc(3), read(2), stat(2), or realloc(3). SEE ALSO
ferror(3), fgets(3), fopen(3) STANDARDS
The getdelim() and getline() functions conform to IEEE Std 1003.1-2008 (``POSIX.1''). BSD
June 30, 2010 BSD

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GETLINE(3)						     Linux Programmer's Manual							GETLINE(3)

getline, getdelim - delimited string input SYNOPSIS
#define _GNU_SOURCE #include <stdio.h> ssize_t getline(char **lineptr, size_t *n, FILE *stream); ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream); DESCRIPTION
getline() reads an entire line, storing the address of the buffer containing the text into *lineptr. The buffer is null-terminated and includes the newline character, if a newline delimiter was found. If *lineptr is NULL, the getline() routine will allocate a buffer for containing the line, which must be freed by the user program. Alter- natively, before calling getline(), *lineptr can contain a pointer to a malloc()-allocated buffer *n bytes in size. If the buffer is not large enough to hold the line read in, getline() resizes the buffer to fit with realloc(), updating *lineptr and *n as necessary. In either case, on a successful call, *lineptr and *n will be updated to reflect the buffer address and size respectively. getdelim() works like getline(), except a line delimiter other than newline can be specified as the delimiter argument. As with getline(), a delimiter character is not added if one was not present in the input before end of file was reached. RETURN VALUE
On success, getline() and getdelim() return the number of characters read, including the delimiter character, but not including the termi- nating null character. This value can be used to handle embedded null characters in the line read. Both functions return -1 on failure to read a line (including end of file condition). ERRORS
EINVAL Bad parameters (n or lineptr is NULL, or stream is not valid). EXAMPLE
#define _GNU_SOURCE #include <stdio.h> #include <stdlib.h> int main(void) { FILE * fp; char * line = NULL; size_t len = 0; ssize_t read; fp = fopen("/etc/motd", "r"); if (fp == NULL) exit(EXIT_FAILURE); while ((read = getline(&line, &len, fp)) != -1) { printf("Retrieved line of length %zu : ", read); printf("%s", line); } if (line) free(line); return EXIT_SUCCESS; } CONFORMING TO
Both getline() and getdelim() are GNU extensions. They are available since libc 4.6.27. SEE ALSO
read(2), fopen(3), fread(3), gets(3), fgets(3), scanf(3) GNU
2001-10-07 GETLINE(3)
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