Get a string of characters from a file
#include <stdio.h> char* input_line( FILE* fp, char* buf, int bufsize ); extern int _input_line_max;
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
This function is in libc.a, but not in libc.so (in order to save space). |
The input_line() function gets a string of characters from the file designated by fp and stores them in the array pointed to by buf. The input_line() function stops reading characters when:
In addition, the input_line() function buffers the last _input_line_max lines internally. The _input_line_max variable is defined in <stdio.h>. You can set it before calling input_line() for the first time; its default value is 20. While the line is being read, the KEY_UP and KEY_DOWN keys can be used to move to the previous and next line respectively in a circular buffer of previously read lines. The newline character (\n) is replaced with the null character on input.
A pointer to the input line. On end-of-file or on encountering an error reading from fp, NULL is returned and errno is set.
#include <stdlib.h> #include <stdio.h> #define SIZ 256 int _input_line_max; int main( void ) { FILE *fp; char *p, buf[SIZ]; fp = stdin; /* Or any stream */ _input_line_max = 25; /* set before 1st call */ while( ( p = input_line( fp, buf, SIZ ) ) != NULL ) { printf( "%s\n", buf ); fflush( stdout ); } return EXIT_SUCCESS; }
Safety: | |
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Cancellation point | Yes |
Interrupt handler | No |
Signal handler | No |
Thread | No |