libpbm(3)
NAME
- libpbm - functions to support portable bitmap programs
SYNOPSIS
- #include <pbm.h>
- cc ... libpbm.a
DESCRIPTION - PACKAGE-WIDE ROUTINES
KEYWORD MATCHING
- int pm_keymatch( char* str, char* keyword, int minchars )
- Does a case-insensitive match of str against keyword. str can be a
leading sunstring of keyword, but at least minchars must be present.
LOG BASE TWO
- int pm_maxvaltobits( int maxval )
- int pm_bitstomaxval( int bits )
- Convert between a maxval and the minimum number of bits required to hold
it.
MESSAGES AND ERRORS
- void pm_message( char* fmt, ... )
- printf() style routine to write an informational message.
- void pm_error( char* fmt, ... )
- printf() style routine to write an error message and abort.
- void pm_usage( char* usage )
- Write a usage message. The string should indicate what arguments are to
be provided to the program.
GENERIC FILE MANAGEMENT
- FILE* pm_openr( char* name )
- Open the given file for reading, with appropriate error checking. A
filename of "-" is taken as equivalent to stdin.
- FILE* pm_openw( char* name )
- Open the given file for writing, with appropriate error checking.
- void pm_close( FILE* fp )
- Close the file descriptor, with appropriate error checking.
ENDIAN I/O
- int pm_readbigshort( FILE* in, short* sP )
- int pm_writebigshort( FILE* out, short s )
- int pm_readbiglong( FILE* in, long* lP )
- int pm_writebiglong( FILE* out, long l )
- int pm_readlittleshort( FILE* in, short* sP )
- int pm_writelittleshort( FILE* out, short s )
- int pm_readlittlelong( FILE* in, long* lP )
- int pm_writelittlelong( FILE* out, long l )
- Routines to read and write short and long ints in either big- or little-
endian byte order.
DESCRIPTION - PBM-SPECIFIC ROUTINES
TYPES AND CONSTANTS
- typedef ... bit;
- #define PBM_WHITE ...
- #define PBM_BLACK ...
- each bit should contain only the values of PBM_WHITE or PBM_BLACK.
- #define PBM_FORMAT ...
- #define RPBM_FORMAT ...
- #define PBM_TYPE PBM_FORMAT
- #define PBM_FORMAT_TYPE(f) ...
- For distinguishing different file formats and types.
INITIALIZATION
- void pbm_init( int* argcP, char* argv[] )
- All PBM programs must call this routine.
MEMORY MANAGEMENT
- bit** pbm_allocarray( int cols, int rows )
- Allocate an array of bits.
- bit* pbm_allocrow( int cols )
- Allocate a row of the given number of bits.
- void pbm_freearray( bit** bits, int rows )
- Free the array allocated with pbm_allocarray() containing the given
number of rows.
- void pbm_freerow( bit* bitrow )
- Free a row of bits.
READING FILES
- void pbm_readpbminit( FILE* fp, int* colsP, int* rowsP, int* formatP )
- Read the header from a PBM file, filling in the rows, cols and format
variables.
- void pbm_readpbmrow( FILE* fp, bit* bitrow, int cols, int format )
- Read a row of bits into the bitrow array. Format and cols were filled in
by pbm_readpbminit().
- bit** pbm_readpbm( FILE* fp, int* colsP, int* rowsP )
- Read an entire bitmap file into memory, returning the allocated array and
filling in the rows and cols variables. This function combines
pbm_readpbminit(), pbm_allocarray() and pbm_readpbmrow().
- char* pm_read_unknown_size( FILE* fp, long* nread )
- Read an entire file or input stream of unknown size to a buffer.
Allocate memory more memory as needed. The calling routine has to free
the allocated buffer with free(). pm_read_unknown_size() returns a
pointer to the allocated buffer. The nread argument returns the number of
bytes read.
WRITING FILES
- void pbm_writepbminit( FILE* fp, int cols, int rows, int forceplain )
- Write the header for a portable bitmap file. The forceplain flag forces
a plain-format file to be written, as opposed to a raw-format one.
- void pbm_writepbmrow( FILE* fp, bit* bitrow, int cols, int forceplain )
- Write a row from a portable bitmap.
- void pbm_writepbm( FILE* fp, bit** bits, int cols, int rows, int forceplain )
- Write the header and all data for a portable bitmap. This function
combines pbm_writepbminit() and pbm_writepbmrow().
SEE ALSO
- libpgm(3), libppm(3), libpnm(3)
AUTHOR
- Copyright (C) 1989, 1991 by Tony Hansen and Jef Poskanzer.