getdelim

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



NAME
       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 con-
       taining 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.  Alterna-
       tively,  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 :\n", 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)